One of the demonstrations at the Apollo event demonstrated a nice free music player they developed. It’s from FineTunes.com. You can add a playlist to your website like I did on the bottom right of this site, or you can even place a player on your desktop. FineTunes has a lot of music, it’s free and licensed, as in legal. They don’t have everything, but there is a lot of music there.
My playlist is kind of eclectic, don’t hold it against me.