Well, I found a file called 'favorites.dat' in \USER\UserData\iGo\save. I opened it with notepad and found that it lists each of the favorites, but only that. No information about the locations of these favorites, nor any link to a database containing locations. I'm assuming that by deleting any of these names it will eliminate it from the favorites listing, but I will keep a backup just in case.
I will keep looking around for a file that has the location information, there has to be something somewhere.