Nomad makes a device called a jukebox with gigabytes of storage.  It's about
the size of a cd player.  It will hold all your music and will feed into an
auxiliary jack on your radio.  I use a Blaupunkt Reno with Thummer Remote
and feed the Nomad output to the aux input.  Nomad has playlists and a
database that you can manipulate and change via your PC / USB.
Nomadworld.com is the URL.

p