vi /etc/X11/xorg.conf (or wherever Fedora keeps it)
I always make a backup of the file before I go tweaking. As far as getting the rez you want, if you've got the correct refresh rates and card/driver you should be okay. That said, my display looks good at 1024x768 and then looks goofy as hell and would require significant modelining until I get to 1600x1200 and then it looks good again. *shrug* So if you're not invested in precisely 1280x1024 and you could go higher, you might try that.
(Oh, and actually, Fedora may have some specific tool that even works in text mode, but the above are the generic ones.)