It might be that you card is supported by linux, but not properly configured. Try running
as root from a console (having closed any applications that use the sound card, such as xmms). That should load the correct kernel module, or at least its best guess. Then, if you hear nothing, as root, run
and unmute any muted channels (especially master and pcm) by pressing the m key and turn the volumes up, then run
to save your changes.
xmms is essentially based (in terms of look and functionality) on old winamp. Since I used winamp when I used windows, I haven't tried any other audio players. I've heard good things about amarok, which I think also has support for ipods.
Hope this helps.
edit: too much to type, too little time! rickh is right re: xmms too!