Good luck with the Redhat 8 Adventure! It's a good distro to bring on if your new to the GNU/Linux thing. If you have mp3s, you'll have to install a package, available on
www.xmms.org 's front page. By Default, Redhat doesn't support Mp3 format. RH8 doesn't come with a video player either..
www.freshrpms.org - download 'mplayer' and install that. Before you do, it'll ask for like 10 other packages to install first. go back to freshrpms.org and download them all and THEN the mplayer package and you'll have a bad ass video player that can play nearly every popular format out there.
the 'search' option here will be your BEST friend