Royalty Free Music Wav

Is there a site where you can download free tracks to use in making your own CD?

I want some background music with harps or violins or guiltars or even techno. But I don’t know where I can get copyright free, royalty free, free tracks in WAV format that I could use in layers beneath my voice.

Does anyone know any place where they offer them? Not songs, just musical tracks using various instruments.