It has been announced recently that Banshee (the default media player) will include 2 music stores in 11.04. Banshee will have both the Ubuntu One Music Store and the Amazon MP3 Store. 75 percent of profits will go to Ubuntu and 25 percent will go to GNOME. GNOME will also get 25 percent of profits from the Ubuntu One Music Store in Rythembox music player.
Sales from the music stores will help support Ubuntu, so when 11.04 comes out check out the music stores and see if there is any music you like.