Mp3, wma formats are copyrighted formats. Not everybody knows that they are breaking a bunch of rules and copyright patents by playing and redistributing fileformats like mp3 and wma. The big companies are smart here by integrating their formats in their players and operatingsystems by default but they are not granting u as a user to do what you want with the music and other data that it produces.
Thats why i recommend all of you to convert your music archive to Ogg vorbis. Ogg Vorbis is a open and patent free format that gives you all advantages that opensource softwares provides. All the most common players are supporting the ogg format (Winamp, VLC etc). On the Ogg vorbis homepage you will also get links to software you can use on the most common operating systems.