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.

Search Tools Consulting explains how the search engine programs called "robots" or "spiders" work, and reviews related sites.

A listing of open source indexers, including links to related articles.

PLS's search engine and products, accompanied by complete documentation, are available for download from this website.

An up-to-date overview of research in the field of information retrieval.