Streamtuner is still with us; but, XMMS did not make the cut. Here's how to change the default player and, hopefully, get your tunes back. This came from a post I found in the Ubuntu forums. I'm just passing it on. I'd would have liked to have given credit to the original poster.
1). Install and open Streamtuner
2). Click on Edit and then Preferences.
3). Remove the two instances of "xmms %q." Substitute the name of your preferred player. For instance: amarok %q
4). IMPORTANT: 1). NO capital letters. 2). DO NOT forget "%q" after your players name. (I have done both of these and it don't work with these errors.)
That's all there is to it. Enjoy!