I need some help uninstalling AVG search toolbar; it came cloaked in an update to AVG Free security software and the installation popup doesn't state that a search toolbar will be added to the browsers installed.

I have Windows xp professional; I've run regedit and deleted the folders related to these from HKEY LOCAL MACHINE and HKEY USER. There are folders for AVG toobar (or whatever the name is) and for Yahoo. The installation changes the search default in the address bar for Firefox to Yahoo. I don't know what else to look for; I can't find a reference to this addon in the main AVG software registry. The next thing I suppose I could try is to unistall AVG and then be more careful about installation and updates.