I was using Testdisk in K oppix but I'm sure this applies to Ubuntu.
I can find files on the bad partition using the directory tree. I hit c to copy the file and then Testdisk wants the destination folder.
Every example video or instruction page says I should be seeing a direcotry tree on my destination drive. I don't but the destination drive shows its mounted.
81 Answer
I'm not sure where testdisk is looking, but it should be able to browse right from your root directory to anywhere (if it's running as root/sudo), and it usually only targets devices for working on, not mountpoints, maybe that's the problem?
apt-get should definitely install testdisk, it's in ubuntu's universe repository, maybe universe isn't enabled in your sources so it's not showing up? dpkg -i can install downloaded .deb files too, though usually apt is easier / safer.