Although it won't necessariy get rid of it all, run AdAware
It will identify browser hijacks and trojans, but you may then need to run special tools for this particular infestation. No virus scanner finds all virii, according to a research paper (about 4 months ago, I seem to recall).
I de-infested a friend's system a month ago (although I berated him for clicking on links and attachments in emails) - took me 2 days, and a full suite of tools - some free, some not.
Cheers
PeteS