For that price, I really like the Music Hall 25 (can't remember the exact model). Better than others at that price range (warmer sounding). CD players are something I would personally buy new rather than used.
If you're at all into computers and have a decent computer with plenty of hard disk space, consider using your computer as the source. The Slim Devices Squeezebox is just an awesomely supported unit that can do just about anything. Once you are used to having all your CDs in one place, you'll never go back. You can get started for $300 for the squeezebox. Later add an external DAC and you'll have a better-sounding unit than the Music Hall, and move convenient to boot.
I have the Olive Musica and am very happy with it (especially with the upgrade, released today, that let's me control playback from any web browser). Simpler setup and fits right in my stereo setup and records from LP -- but list is $1500. Sound quality of the squeezebox is just as good.
Best of luck, it sounds like you are on the way to a nice system.
- Eric