Welcome to the pack!
Rhythmbox play Internet streaming radio
I use VLC player, simple and lite. Firefox handles it neatly. Once installed, you may need to tell Firefox to use the VLC player. Hit Ebit-Preferences-tab Applications- choose mp streaming and mp3 shoutcasr, select "use vlc" and you're set! By the way, you may need to install it, look in the software center under "applications" (if I'm not mistaken)...just a suggestion.
Hmm,a bit tight, but an external drive should help you out for the not-so-active stuff...
Great to have you around!