Songbird is a free and open source software media player and web browser. I use this player myself and think that Songbird is all you need for listening to your music files and more…
* Ability to play multiple audio formats, such as MP3, AAC, Ogg Vorbis, FLAC, Apple Lossless and WMA
* Ability to play Apple FairPlay-encoded audio on Windows and Mac platforms via hooks into QuickTime (authorization takes place in iTunes)
* Shout Cast Radio and Last.FM
* mashTape (Discover Flickr photos, YouTube videos, last.fm biographies, Google news for the currently playing artist.)
* 7digital Music Store (Buy high quality MP3s (320kbps) and get recommendation for new tracks based on your listening habits.)
More info here.
Download here.