[Help] i got a virus from this site i believe..

Well, i got a virus on my computer today. Norton popped up a little alert while I was playing CF earlier that warned me that i had a virus. So i clicked fix and it said problem resolved then a few minutes later another alert popped up and said the same thing so i clicked on fix again. Since then i haven't gotten any more warnings (i ran a full system scan) but i'm still a little worried.

It's called Backdoor.IRC.bot And according to Norton 360 it's infected 83 host files, a handful of programs, 164 registry files and a few cache files. Anybody know where it could have come from/ what it can do to my computer/ how to get rid of it??

I've already gone into the hosts file to check but there were no issues with it that i could tell. And i ran CCleaner on my registry to see if that would help at all but no dice there. Any suggestions or pointing me in the right direction would be appreciated.
Thanks

tl;dr I have a virus and need help with removing it.