SEOmoz
- Resource by Rand Fishkin, with weblog, articles and free tools. Includes a beginner's guide, an online exam and recommended firms.
- http://www.seomoz.org/

SEO List
- A directory of optimizing firms and marketing firms.
- http://www.seolist.com/

SEO Consultants Directory
- Lists website optimizing companies worldwide by country, US state, and language. Add and review services.
- http://www.seoconsultants.com/

Sempo
- A non-profit professional association offering case studies, articles, events and comprehensive directory of search engine marketers.
- http://www.sempo.org/

SEOpros.org
- Organization of SEOs and marketing consultants developing and implementing a set of best practices for the search engine optimization industry. Includes a database of consultants, consumer tips, SEO skills sets and complaint registry.
- http://www.seopros.org/

Eric Ward
- Specialized internet promotion and press release services for high-end web site launches.
- http://www.ericward.com/

Academy of Web Specialists
- Search engine marketing resources.
- http://www.academywebspecialists.com

Pandia
- Guide to Web searching and search engine optimization, with tutorials, news, tools, reviews and SE marketing resources.
- http://www.pandia.com/

Majon International
- Offers targeted web marketing promotions and advertising including mall linkings, opt-in email campaigns, web site exposure promotions, pop-up and pop-under advertising, and press release distribution services.
- http://www.majon.com

Reciprocom
- Advertising package available in a high quality print format or as a state-of-the-art multimedia CD-ROM to reach targeted e-commerce consumers, through pooled consumer lists.
- http://www.reciprocom.com