Certification Vendors
Check Point
Cisco
Citrix
CIW
CompTIA
IBM
(ISC)2
Linux Professional Institute
Lotus
Macromedia
Microsoft
Novell
Planet3 Wireless
PMI
Oracle
Red Hat
Sun
Testing Centers
Prometric
Vue
Communities/Information
CertCities
Certification Magazine
MCP Magazine
Practice Test Providers
Self Test Software
Transcender
Training Facilities
New Horizons
* Note that this list is not meant to be exhaustive, but merely to provide a starting point for those interested in learning more about IT certifications. If you know of a resource that you feel would be beneficial here, then please let me know.