The Mardox Network
Composed of about 16 different companies offering web related services

Direct Email List Source
The free Web directory of opt-in email lists for advertisers and marketers.

1234 Find Web Designers & More
Directory of marketing and web site promotion businesses, e-commerce resources, and design consultants.

WebMarketingWatch.com
Directory provides links to web marketing information such as newsletters, forums, and articles.

Web Marketing Directory
A directory of web marketing companies from the U.S. that offer services including search engine optimization, banner advertising, and email marketing.

Addto E-commerce and Internet Marketing
An e-commerce and web marketing directory offering advice, software, services and tools for online business.