First-Zone - Directory page with PPC links. - http://www.first-zone.com/
Webtotal Internet Directory - Directory and search engine of pay per click and businesses websites. - http://www.webtotal.biz/
UrlHit.com - Marketing resources, pay per click search engines (ppc) link exchanges and domain names. - http://www.urlhit.com/
PPC-Directory.com - Complete directory of PPC and Pay Per Click Search Engines with hundreds of listings, tools, free PPC's, and reviews. - http://ppc-directory.com/
Hit44.Com - Over 44 specialized pay per click search engines. Save time and find specific websites with one click searching. - http://www.hit44.com