Why do you want to install GTalk in Fedora Linux 13? If you want to install it for chat purpose, then do install chat clients like empathy, pidgin, etc which do their work very well. I have used both very well, & I never felt the need to install Gtalk in Fedora Linux 13!
IMO, everything you install in Fedora Linux should be in .rpm files, so I don't know whether Gtalk will be available to you directly. But if these chat clients are helpful in purpose, then I will be happy!