xmms, it has lots of dependencies though, I would think any player would support mp3's, check what libraries are installed on your system, most linux distros support any sound format----->ogg,flac,mp3,wav whatever
oh ya, i think ubuntu uses debian packages or something, maybe "apt get", not sure, you should be able to just download and install it without compiling it
check ubuntu's website, I cant keep up with all the linux forks and offshoots anymore, the 4 main distro's are hard enough to keep up with