Do you know of a good winamp equivalent for xubuntu?
If you just want Audio, Amarok is great. Don’t know anything about xubuntu though.
I know of two: VLC (also lets you watch Shoutcast TV video streams) and Rhythmbox (lets you add/bookmark Shoutcast radio streams). Exaile should also work.
For Xubuntu, I’d pick either Rhythmbox, Exaile, Listen, Amarok, or the Beep Media Player. XMMS is a straight-forward clone of Winamp, but development of that stopped a long time ago, so I wouldn’t recommend it.
However, you can install Winamp on Xubuntu provided you have a fairly-recent version of Wine (along with Wine Gecko). The latest version of Wine is 1.1.23. It supports a LOT of Windows-based programs.