%APPDATA% is a windows environment variable that holds the location where all the application data is stored. The linux equivalent is generally your home directory.
But to save you the effort, your Firefox profile directory is generally "~/.mozilla/firefox/<randomprefix>.profilename/".
As of FF3, the browser history and bookmarks are now stored in an sqlite database file called "places.sqlite", stored in the main profile directory.
On the other hand, it sounds to me like you haven't even gotten the rescued partition mounted correctly yet, since you say you don't have any files listed at all.