Bill, Yes, I have. Most of them work well, the only caveat being that they (generally) need to be installed before you start installing/removing other programs - this is to enable them to see what is going where, so that they can make sure that all the bits of the other programs are removed correctly. So, this may not help you at this time.
I assume you're using one of Windows many variatons? Windows is a real bugger for dropping bits of code anywhere and everywhere and then conveniently forgetting to remove them, even in its latest XP variation (and I actually don't mind XP - my system has been very stable since I started using it). I have developed the habit of backing-up everything I need to save that I don't have copies of (documents, pix, downloaded programs etc) then nukeing the HDD every so often and re-installing everything clean - this is a hang-over from the bad old Win98 days (c: I used to need to do it every 6 months or so with 98, but XP seems to be a bit better at housekeeping. It's coming due though.
If you have the skill and time, then vape the HDD and start anew - bestest way. If you want to use one of those programs, then do a bit of research - the software may have developed to the point where it can clean bits of code up without needing to know where it came from. Start with the publisher's websites and go from there.
Best of luck
RobG (The Aussie One)