I installed the DVD-R/RW drive that my bf gave me into my iBook last night.
I swapped the bezels too so it fits perfectly and looks like a normal iBook drive.
It is a Toshiba SD-R6112 2x DVD-R etc etc. Burns best with Toast and iTunes so far. It burns with finder but has trouble at the end of the session and with validating. I'm not sure why, so for now, I'm sticking with toast. I haven't gotten ahold of iDVD to try that yet. But iTunes works fine.
I submitted my review to www.xlr8yourmac.com's drive database. It isn't up yet though.
So now, my formerly iBook 600/combo is an iBook 900/superdrive 
mmmmm
- Alison