Here are 138 blogs that talk about B2B marketing, as well as a few that focus on selling, search engine marketing, and copy writing. I will update (add or remove) the list as I change the B2B marketing blogs that I track.

Also, here's an OPML file of these B2B marketing blogs. (Right click and and save-as, then import to your reader). If you have a blog that is relevant to B2B marketers and provides a unique perspective or content, then let me know by linking here so I can add you to the list.

Big List of B2B Marketing Blogs

• 10,000 Marshmallows – ViaMetric's blog focuses on primarily on marketing accountability. The name: How do you eat 10,000 marshmallows? One at a time.
• A PR Guy's Musings – Stuart Bruce writes about the science of public relations.
• A Wider Net – All about fresh, new marketing technologies, from marketing agency Cramer.
• Accelerating IT Sales – Barry Harrigan blogs about online strategies that shorten your sales cycle.
• Achieve Market Leadership – Insights on opportunity analysis; strategy and planning; and operations and execution, by the Crimson Consulting Group.
• Aggressive Small Business Marketing – Big thoughts, ideas and how-tos for aggressive, fast-growth businesses and the entrepreneurs who fuel them, by Michael Cage.
• Anything Goes Marketing – Chad Horenfeldt shares tips and tricks to improve your online marketing skills.
• Approvr Blog – Topics in marketing operations, including managing proofing and approvals.
• Arketi B2B Marketing Minute – Podcast that covers news, ideas and best practices for business-to-business marketing professionals.
• Ask Justin Hitt Blog – Addressing challenges faced by Sales and Marketing Management of industrial and high-tech business-to-business organizations.
• B2B Email Marketing Best Practices – Tamara Gielen focuses on B2B email marketing from a doer's perspective.
• B2B Growth Marketing - Bill Gilbert writes about moving high tech companies move from a technical focus to a customer-driven brand (inactive).
• B2B Insight - Ephraim Cohen's writes about corporate communications and PR from a B2B perspective.
• B2B International – B2B market research consultancy focused on international issues.
• B2B Knowledge Sharing – Scott Gillum of MarketBridge blogs about the constantly changing world of B2B Sales and Marketing.
• B2B Lead Generation Blog - Brian Carroll's blog focuses on B2B lead generation, sales leads, and marketing for the complex sale.
• BtoB Marketing – Loredana Niculae (based in Romania) shares her experiences on marketing topics for the B2B enterprises and more.
• B2B Marketing - B2B marketing in England and Ireland
• B2B Marketing Blog (German) – Warum technologieunternehmen die macht der marke entdecken sollten (Google translates as: Why technology enterprises should discover the power of the brand).
• B2B Marketing Business And Consumer – Understanding the difference between B2B, B2C, and C2C.
• B2B Marketing Communications 2.0 – Pete Jakob writes that as B2B customers turn to the internet to support all stages of their buying process, B2B marketing needs to change its game - and fast!
• B2B Marketing Confidential - Andy Hasselwander provides news and insights from across the B2B marketing landscape.
• B2B Marketing ROI – Making B2B marketing as sexy as B2C, from Adam Blitzer at Pardot.
• B2B Sales Solutions – Dale Underwood writes about B2B sales topics.
• B2B SEO - Galen De Young blogs about Business-to-Business Search Engine Optimization.
• B2B SEO Blog - Dave Martin shares ideas about internet marketing for B2B companies.
• B2B Web Strategy – eMagine's blog about driving traffic, engaging visitors, conversion, measurement, and internet marketing.
• B2Blog – Dave J uses his perspective as a marketer in the trenches to write about the dramatic changes affecting industrial marketing / B2B marketing.
• B2Bridge.eu –A pan-European community of business and industrial marketers.
• Babcock & Jenkins – Marketing thoughts from this direct and relationship marketing agency.
• Bad Marketing – Todd Ebert tells the good, the bad and the ugly of B2B marketing, and gives ideas for on improving it.
• Bark in B2B Marketing – Extraprise's corporate blog about B2B database marketing and marketing automation.
• BeeToBee – Not a blog… like Digg for B2B Marketing. Check it out.
• Better Closer Blog – Bill Rice's blog gives tips and techniques that will have you turning more prospects into customers.
• Bill Hartzer – Bill writes about corporate website marketing and search engine optimization for B2B companies. (Bill's website is Corporate Website Marketing and his LiveJournal blog republishes press releases about Search Engine Optimization and B2B website tips.
• Biznology – Where business and technology come together (by IBM's search marketing expert, Mike Moran).
• Blogfrey – From B-to-B branding and integrated marketing communications agency Godfrey.
• Bluebird Blueprint – Marketing best practices in from Tricia Reilly at Bluebird Marketing.
• Branding and Marketing – Chris Brown writes for business professionals with an interest in branding and marketing, with a focus on building awareness.
• BriefingsDirect – B2B informational podcasts on information technology subjects moderated by IT analyst Dana Gardner.
• B-to-B Tech Marketing Blog – Conversations about marketing to IT and developers by Pauline Beall of CMP Media (inactive).
• Building a Sales Machine – Aaron Ross writes about accelerating growth, reducing uncertainty, and creating a predictable sales machine in the on-demand era.
• Business of Marketing and Branding – David Koopmans writes about marketing and branding in the Information Age.
• Business to Business Marketing News – From the Arketi Group, a marketing consultancy that helps business-to-business marketers generate revenue and accelerate growth.
• Buzz Marketing for Technology – Paul Dunay from BearingPoint shares innovative ideas and information for marketing technology companies.
• cadenceblog – Ideas, tools, and trends in IT B2B Marketing and Sales.
• Click To Lead – Michael Ortner of Capterra writes this guide to software marketing and online lead generation.
• Crankshaw on Tech Marketing – Online marketing for B2B technology companies. Best practice and lean process.
• Create Value Innovation – All about innovating in ways that matter to customers.
• Customers Rock – Becky Caroll shares a B2B perspective on how businesses can make sure their customer experiences rock.
• CustomerThink – Thought leadership about customer-centric business strategy from the folks formerly known as CRMGuru.
• Dealing with Darwin - Geoffrey Moore (author of Crossing the Chasm and other books on high-tech marketing) writes occasionally about B2B marketing strategy.
• Demandblog – Best practices in B2B demand generation.
• Direct Connections – Howard Sewell writes about best practices & principles in direct response marketing for high technology companies.
• Elevation: From Thought Leadership to Market Leadership – Britton Manasco helps companies develop and tell their stories of customer success.
• Enterprise Software Executive – David Gearhart's blog is dedicated to helping enterprise software executives increase sales and improve marketing.
• Freaking Marketing – Robert Rosenthal shares all types of marketing tips, including B2B marketing and lead generation categories.
• Guerrilla Consulting – Michael McLaughlin helps consultants market themselves with breakthrough tactics for winning profitable clients.
• HR Marketer – A blog for companies who sell products or services to human resource (HR) executives.
• Hugo E. Martin – Developments in the area of print & online media, communication & PR, marketing, Internet & people business (English and German).
• I Confess – Rob DeRobertis shares stories in B2B high tech marketing.
• Idea Sellers – Daniel Sitter writes about better tips for selling.
• Industrial Search Engine Marketing – Blog by ecreativeworks, a web design and search engine marketing /SEO firm focused on Industrial Marketing.
• inmedia Public Relations – Best practices in the marketing of technology
• Internet Marketing Blog for Small Business – The guys at HubSpot share ideas to help businesses leverage modern marketing practices and the Internet for lead generation and increased sales.
• Jim Logan's Blog – B2B Consulting and Copywriting
• Knights on the Road – Articles and book reviews about the new world of sales.
• Know New Marketing – Ken Pulverman of Oracle shares how to use Web 2.0-based marketing techniques to reduce sales cost and cycle time.
• Launch PR – Schneider Associates explores strategies to launch new products, services, companies, and communities.
• LeadBuying.com – Conversations on lead buying, including a blog and an open forum and wiki.
• Life as a B2B Technology Marketer – Paul Woods is a Marketing Technologist based in Brisbane, Australia.
• Manhattan Marketing Maven – Danny Flamberg shares practical hands-on marketing and advertising tips.
• Marcom Writer Blog – Dianna Huff delivers news, riffs, and commentary on all things relating to B2B marketing communications.
• MarketCapture Blog - An idea-exchange for B-to-B software marketing executives. Topics include marketing strategy, lead generation, and marketing metrics.
• marketfusions – Shivonne Byrne's thoughts on strategy, business, marketing, content & creativity.
• Marketing Fishbowl – Gary David comments on all things marketing, from the elementary to the profound.
• Marketing in a Web 2.0 World – One marketer's quest to define, explore, experiment and determine the value of B2B Social Media Marketing and Marketing 2.0.
• Marketing Interactions - Ardath Albee writes thought-provoking posts about marketing and sales integration, shortening sales cycles, and improving sales tools.
• Marketing MO – Marketing tips from the trenches for B to B marketers, executives, entrepreneurs & consultants.
• Marketing Monitor – Search Engine Marketing articles from Enquiro.
• Marketing Operations at Work – Marketing Operations Partners blogs about the emerging discipline of Marketing Operations.
• Marketing Productivity Blog – Jim Novo writes about moving from a low accountability to high accountability business model.
• Marketing Today – Peter DeLegge blogs about marketing with special attention given to internet marketing and business-to-business marketing issues and trends.
• Marketingland – Dutch B2B marketing and sales weblog, by Henri van den Hoof.
• McBru Blog – From advertising and PR agency McClenahan Bruer Communications.
• Mediapace – From American Business Media, the association of business information companies.
• Modern B2B Marketing - Jon Miller shares Marketo's latest thinking about B2B marketing, from best practices in search engine marketing to lead nurturing to marketing accountability.
• MSC Marketing – B2B sales ideas from Mike Carroll at MSC Marketing, a B2B sales and marketing consultancy. 
• My Educated Guess –TechTarget’s Client Consulting Team blog about topics such as branding, positioning, and lead generation.
• NxtERA Marketing Blog – Elana Anderson’s musings, ideas, and — sometimes — random thoughts about data-driven marketing.
• One Riot - One Ranger – A discussion of interim management (flexible staffing) for B2B marketing functions by Charles Besondy.
• Online Fluency – Helps business-to-business marketers understand blogs and social networks, from Makovsky + Company.
• Opinionated Marketers – Maureen Rogers and John Whiteside share their opinions on marketing (not all B2B).
• Out of my Gord – Gord Hotchkiss blogs about Search Engine Marketing for B2B companies.
• Pacifica Group – Sridhar Ramanathan writes about driving revenue growth for technology firms.
• PowerPR - B2B Marketing – Business to business relations as they relate to marketing.
• PPC b2b – News, articles and tips from the Web Marketing world.
• PR2.0  – Brian Solis' blog fuses public relations, social media, and new media marketing.
• Sales Tools and Sales 2.0 - Fresh ideas and motivation to help sales professionals and managers sell more.
• Rebecca Caroe – Rebecca writes about business development, marketing and sales for marketing agencies.
• RefreshWeblog – John Rasco blogs about B2B web marketing and SEO news.
• Revenue Journal - Kristin Zhivago's writes about revenue-increasing insights, strategies and techniques for CEOs and entrepreneurs.
• ronbrauner.com – Ron shares his marketing advice.
• Sales Itch – Ed McLean writes about the changing world of Sales, with occasional posts about sales-marketing alignment (inactive).
• Sales Lead Insights - Mac McIntosh blogs about ways to boost your business with B2B marketing and B2B sales lead generation.
• Savvy Internet Marketing – Pam Swingley discusses internet marketing for technology and B2B firms.
• Selling to Big Companies – Jill Konrath's step-by-step guide for sellers who want to get their foot in the door of large corporations.
• SEO-Space – Organic search engine marketing thoughts and insights with a B2B twist.
• Shiblog– Prescott Shibles shares B2B internet marketing and media insight.
• ShopTalk – John Caddell gives a daily look at business-to-business marketing, highlighting trends, focusing on what works and what doesn't.
• Simplenomics – Mike Sigers blogs about sales, marketing and customer service the Simplenomics Way.
• Six Sigma Selling – Michael Webb writes about improving sales processes, including sales and marketing integration.
• Small Business B2B Marketing – Scott Thompson occasionally writes about marketing trends & insight for small business-to-business companies.
• Small Business Marketing – From B2Bsearch.org, a business to business directory for small business marketing and corporate branding.
• Starr Tincup – Starr Tincup is an integrated marketing firm for business-to-business software and services companies.
• Startup-Marketing -- Working with Startup CEOs and Marketers to Explore the Keys to Startup Marketing Success, by Sean Ellis.
• Stupid Marketing – Kevin Epstein promotes great marketing and shins a spotlight on the spectacularly stupid things that sometimes get committed in the name of marketing.
• Stu's Blog: Success Stories to Grow Your Business – Marketing frameworks, best practices, and smart tactics for Demand Generation, Sales Optimization, and Customer Success.
• SynaxisSpeaks – Applications of philosophy to marketing and branding.
• The B2B Lead – Real world, practical B2B sales and marketing tips from ReachForce.
• The Business Of Business Marketing –Mike Bawden writes about insights, information and advice on B2B marketing and brand building (inactive).
• The Complex System – Jeff Solomon’s Blog about sales lead management, software automation, business strategy & personal methodology.
• The Credibility Branding Blog – Jennifer McLean blogs about accelerating sales through credibility.
• The Innovative Marketer – Steve Gershik shares news and developments from the demand generation industry.
• The Lonely Marketer – The small company Marketing Manager can be planning print advertisement and mailings in the morning and discussing blogs and optimization over lunch. Patrick Schaber discusses these topics and everything in between.
• The Marketing Excellence blog – Eric Kintz of HP discusses key industry trends (such as the social web) and best practices in building the future Marketing function in the tech industry.
• The Olin Report – Examination of customer acquisition strategy and tactics and the impact on sales and marketing process alignment.
• The Scrappy Software Marketer – Andrew Kordek shares thoughts, expressions and general tidbits of being a scrappy software marketer.
• The Social Media Marketing Blog – Scott Monty's perspectives on B2B implications of social media - the convergence of marketing, advertising and PR on the Web - for marketers, agencies and companies.
• Todd Miechiels – Todd is a B2B Internet marketing consultant for small to mid-market B2B companies in competitive industries with long and complex buying cycles.
• Tyco Blog – Tim Young, formerly of the B2B Lead Generation & Management Blog, writes about sales, marketing, and strategy for business owners and executives.
• UsefulArts.us – Dave Wieneke writes about the intersection of online strategy and legal thought.
• Velocity – All about marketing for B2B technology companies.
• vSente's Blog –Ideas for waging and winning battles for market share, courtesy of Mike Smock.
• Web Business Marketing Blog – Aimed at the b2b marketing manager inside a technology-oriented company or non-profit organization.
• WebMama's Look at the Web – WebMama, aka Barb Coll, focuses on search engine marketing for B2B companies.
• WebMarketCentral Blog –Tom Pick has been a b2b marketer since 1992, with an emphasis on research, writing, leadership and online marketing.
• Writing Whitepaper's Blog – Michael A. Stelzner shares the latest trends in writing and marketing whitepapers.

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