Brief Search Engines Guide Logo
Google
Search WWW Search mimech.com
Major Pay-Per-Click Search Engines Listing
Major search engines do not sell paid listings within their main results, or if they do so it is especially mentioned, often as "paid listings" or "sponsored results". At pay-per-click search engines advertisers can bid to be listed at the top of listings with search results. Should you avoid them because of this? Of course not, pay-per-click search engines are very useful especially if you look for some products or services.

Some of the most popular paid search engines are listed bellow:

Google AdWords offers a cost-per-click (CPC) program that places AdWords ads on search results pages in Google and Google Network sites.
Yahoo! Search Marketing is the oldest pay per click search engine (formerly Overture), which produces relevant results, it incorporates its paid listings into some of major search engines.
FindWhat.com is an important pay-per-click search engine with results incorporated into many metacrawlers search results. Bids start at $0.01.
Kanoodle offers a paid search listings with distribution to a large network of other search engines and search box providers. Bids start at $0.01.
Sprinks: Pay-per-click searching service provided by About.com that sends links to some meta search engines, and the Sprinks site itself.
Search123: Pay-per-click search engine that incorporates its paid listings on the sites of some traffic partners.
Xuppa is a paid search placement service with distribution on some metacrawlers. Previously named as Bay9.
Ah-ha.com powered by FAST Search, allows paid listings to appear at the top of its results.
ePilot.com is a pay-per-click search engine which distributes its results on many search partners. Bids start at $0.01.
ValleyAlley: Pay-per-click searching service that sends links to some meta crawlers. Bids start at $0.01.
Win4Win: A paid search engine, which provides top listing for advertisers in its results.
theInfoDepot.: Pay-per-click search engine that uses Open Directory Project database.
eFind.com allows advertisers to bid for the top of listing with search results.

See at Open Directory Project for a more complete list.