Alt Search Engines
- Charles Knight maintains a list of the top 100 alternative and niche search engines. Includes news, reviews and debates on search engines.
- http://altsearchengines.com/

OpenSearch
- A collection of simple formats for the sharing of search results. Includes specifications and frequently asked questions.
- http://www.opensearch.org/

Topix: Search Engines News
- News on the search engine industry continually updated from thousands of sources around the Net.
- http://www.topix.com/business/search-engines

Those Dark Hiding Places: The Invisible Web Revealed
- Librarian Robert J. Lackie provides annotated links to directories, searchable sites, databases, and search engines useful for uncovering content that the general search engines fail to disclose.
- http://www.robertlackie.com/invisible/index.html

FTP Search Engines
- Rated links to ftp and mp3 search sites.
- http://www.ftpsearchengines.com/

CyberTimes Navigator
- The starting point that New York Times reporters and editors use for their explorations of the Web. A straightforward list of some of the best sources on the Web for all types of information.
- http://tech.nytimes.com/top/news/technology/cybertimesnavigator/index.html

Indexing the Internet
- An essay by John Hubbard analyzing the question of what is the best way to index the Internet, with references.
- http://www.tk421.net/essays/babel.html

The Ultimate Search Engine Links Page
- A directory of search engines: general, metasearch, pay-per-click, children's, subject, country and people search. All are described and can be rated.
- http://www.searchenginelinks.co.uk/

Search Engine Showdown
- A user's guide to Web searching with features, comparative analysis, strategies, discussion, news and reviews.
- http://www.searchengineshowdown.com/

Search Engine Colossus
- Directory of hundreds of search engines, organised by country and topic.
- http://www.searchenginecolossus.com/

Complete Planet
- Directory of databases and specialty search engines from Bright Planet.
- http://www.completeplanet.com/

Search Engine Relationship Chart
- Bruce Clay's pictoral view of how search engines provide data to partner engines and directories. Requires Acrobat Reader.
- http://www.bruceclay.com/searchenginechart.pdf

Search Engines Worldwide
- Search engines sorted by geographical location.
- http://home.inter.net/takakuwa/search/

ISEDB
- A directory of search engines and directories worldwide, organized by geographical area and subject, includes articles on site submission, marketing, and optimization.
- http://www.isedb.com/

Fetchfido
- A graphical interface of links to search engines. Multi-layered, with universal, United Kingdom, United States, European and worldwide sections.
- http://homepage.ntlworld.com/fetchfido2/interface/search_engines_universal.htm

FinderSeeker
- Find the search engine you want by selecting a thematical category and/or country, or search by keyword.
- http://www.finderseeker.com/

Searchenginez
- Search forms for the most effective engines in dozens of categories from Robert Skelton. Includes reviews, ratings, webmaster tools, and tutorials.
- http://searchenginez.com/

Direct Search
- Gary Price's compilation of links to the search interfaces of resources that contain data not easily or entirely searchable/accessible from general search tools.
- http://www.freepint.com/gary/direct.htm

Geniusfind
- Categorizes thousands of the most useful topic-specific directories and databases, with descriptions.
- http://www.geniusfind.com/

Search Tools for Web Sites and Intranets
- 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.
- http://www.searchtools.com/

Big Search Engine Index
- Directory listing hundreds of search engines, categorized, described and rated.
- http://www.search-engine-index.co.uk/

Aleph Search
- A directory of directories. Links to selected information rich web resources, both unspecialised and specialised, with a strong emphasis on United Kingdom based sites.
- http://www.alephsearch.co.uk/

Age of Dot Com
- Links to search resources including start pages, integrated search forms, portals, engines, guides, and directories. Offers both a simple links page and a directory with descriptions and ratings.
- http://www.ageof.com/