http://www.extremeoverclocking.com/
http://www4.tomshardware.com/guides/overclocking/
http://www.sysopt.com/ocdatabase.html
There's allot more sites out there but these are some of the better ones. Hope that helps, I wouldn't do it unless I read something kinda formal in one of these forums above. At least the information will be somewhat more reliable.
