Here you go, Larry. These locations are for XP.
C:\Program Files\Mozilla Firefox
C:\Documents and Settings\Owner\Application Data\Mozilla\Firefox
C:\Documents and Settings\Owner\Local Settings\Application Data\Mozilla\Firefox
Substitute your user name for "Owner", if necessary. Also, Application Data and Local Settings are hidden folders. In order to see, open any Windows Explorer window (My Computer will do), select Tools > Folder Options... > View tab > select Show hidden files and folders > click Apply, then OK.
Lancer