Having had to clear my daughters' machines a couple of times bookmark this page:
http://www.spywareinfo.com/~merijn/forums.php
The people there know stuff. Lots of it.
You can't answer in most of those forums until you really have proved you know precisely what you are doing - and it's hard work just learning let alone guiding others.
There are many useful links too. It's well worth some of your time.