My sympathies for those with infected computers. Unfortunately I know the feeling all too well.
I found this useful article on How to Know If Your Computer Is Infected which deals with finding ALL of the nasties. It is not a simple process but should allow you to finally clean out even the most stubborn infection.
How to Know If Your Computer Is Infected. I just used the root kit killer (because I know and trust Kaspersky) and was pleased there was nothing.
A great programme which I used a couple of weeks ago is Hitman Pro, written by some Dutch people. Despite its fearsome name, they claim it as a second opinion scanner, "designed to rescue your computer from malware (viruses, trojans, rootkits, etc.) that have infected your computer despite all the security measures you have taken (such as anti virus software, firewalls, etc.)". I am very pleased with it because it found a trojan that had got past all my defences and was uploading large amounts - probably a botnet. One warning though - after running Hitman Pro you must restart the computer so it can finish because it seems to lock off most ports and internet connections while it is running (I guess to protect itself) and my email and browser all stopped until the computer rebooted. Then everything was fine.
HitmanPro 3 - SurfRight
And finally, when I was looking for software to solve my problems, my Google search threw up a lot of sites which just didn't feel right - their address wasn't quite kosher or the wording on the page was a bit odd. I wonder if some of these sites that have software which promises to fix things are in fact sites containing malware. For that reason, I have deliberately given the 2 web addresses above because I have checked them out pretty closely and have used their software and both sites seem reasonable and safe.