Try PrevX. It does require a payment IF you want it for more than 30 days, but works 100% in the trial period and allows you to remove what it finds, unlike some of the other BS out there.
It's not found by searches, since it's only downloadable by recommendation. You can find the home by typing Prevx into google.
Get that, and run it. I don't know the physics behind it, but it has found things for me and some previous clients that AVG, Spybot, Hijackthis nor AdAware could find.
Simple interface, just as logical as the rest.
Hope it helps anybody.
Dan.