if you are looking for a single-CD, they are generally VERY cheap on places like eBay, since they are the lowest factory option. You can also try a junkyard.
Other than that, I'd say it's a perfect time to go aftermarket, you get much more bang for the buck (did you know that 6-cd player is a $600 option?) For less than half that cost I got an alpine deck that plays mp3s off the disc AND the iPod changer attachment. PM me if you want $20 off at crutchfield, they include all the installation kits, wiring kits, instructions, and usually free/cheap shipping.
_________________
Jeff 2005 Jeep Liberty Renegade
4x4, 6spd, Leather, Sunroof, trak-loc, skids/rails, hitch+shackle, hooks, Alpine/iPod, Thule, GPS, CB, Frankenlifted w/ 31" MTRs
Photos Cardomain