Not many, I'm afraid. What I would probably do is install and run Ewido, and maybe Asquared scanner. If no luck run a Hijack This scan (see the sticky) and see if anything is sus.
I've read that it's a good idea to have more than one spyware scanner, in addition to AV. I'm running 2 background scanners (Ewido and MS Antispy), 4 prevent-settings-being-changed type scanners, (Spybot's tea-timer, SpywareGuard, SpywareBlaster, and Winpatrol) and also regularly scan with Spybot, AdAware, Asquared, Bazooka, and CWShredder.
Having had to have the OS reinstalled and losing data has caused this ounce-of-prevention approach.