Categorizes thousands of the most useful topic-specific directories and databases, with descriptions.

A directory of search engines and directories worldwide, organized by geographical area and subject, includes articles on site submission, marketing, and optimization.

An essay by John Hubbard analyzing the question of what is the best way to index the Internet, with references.

List of search engines and directories. Also includes a metasearch engine, search tutorial, and a free newsletter.

Directory of hundreds of search engines, organised by country and topic.

Bruce Clay's pictorial view of how search engines provide data to partner engines and directories.

A user's guide to Web searching with features, comparative analysis, strategies, discussion, news and reviews.

A guide to search engine marketing and search engine optimization. Forums, reviews, articles, ratings, and frequent newsletters. Paying members receive access to extra content.

Search engines sorted by geographical location.

Provides information, news and advice about web site searching technology. Includes a guide, search tools list, glossary, and opportunity to compare searches of its own site by different tools. Offers a free monthly email newsletter.