I'm using a Sony CRX880A, $40 on eBay. It reads both audio and data CD after the needed modification to the connector. Which you can find here:
http://www.mpc-forums.com/viewtopic.php?f=21&t=69586. But, it will not write/burn CDs which I read is due to the fact that non-Akai drives won't do so if there is a hard drive installed as well (I read that it will however read and write if there is no hard drive install, I think without the connector modification; don't quote me on that).
There is also the TEAC DW-224E which a lot of people have said they use, which initially purchased and returned because I didn't know about the connector modification.
There are a lot more out there, there is just a specific type that you need, which I can't remember the specs of right now. Look around the forum, there has been a few threads discussing this.