Alpine CHAS-634 Car CD Changer i got mine at 

At LOGJAM ELECTRONICS I got an Alpine KCA-130B Ai-NET to M-Bus Adapter (cable)
and a Soundgate ABMW35V5 Alpine CD Changer Interface

Pros: Installing was real easy.  We used velcro to attach the AiNET to the finder well. Plays great have had no problems so far...

Cons: Had to drill four holes on the right side (under the removable side panel) to mount the CD changer. Also drilled a hole in the removable panel for wire.