I just completed adding an internal cd-rom drive into my webplayer. It is a very tight fit, but works. It does bind occasionally when ejecting but I think I just need to trim the plastic piece down a little more.
Here are the stats and the parts list. I have pictures of this and will be posting them soon.
Teac CD-224E 24x CD-ROM
You need a connector for it. The first link has a good picture of it, but this other place has it a LOT cheaper.
http://www.baber.com/baber/products/slimline_cd_adapter.htm
http://www.cablesgroup.com/product_info.php?products_id=751
This will allow you to connect it to a 40 pin IDE. The problem is that we have a 44 pin IDE. A 44 pin IDE is a 40 pin cable (but smaller) and 4 wires for power. I ended up making a special cable for it. Ill include the parts list for the place where I got my parts from, but the shipping is a killer from this place.
I got 2 of these (one for my hard drive and one for the connector to the board). 44 pin female socket
http://www.cablesonline.net/44pinfemidcr.html
I got one of these. 40 pin female socket. I believe this was the part I ordered (I messed up the first one and just pulled one of these off of a regular IDE HD cable)
http://store.yahoo.com/cablesonline/40pinfemidcs.html
Then ordered 2 feet if this cable.
http://www.cablesonline.net/1foot44pin20.html
I then crimped one of the 44 pin female connectors to the end of the ribbon cable and put the other 44 pin to the middle of the cable (actually it was only about 10 inches from the one connector to the other. I wanted more room for the cdrom end).
The last end was a bit tricky and took me 2 tries. I shredded the remaining end of the cable down about 2 inches. You might want to go down a little more than that, it was hard for me to connect it with only 2 inches. Then on my successful attempt, I used a mini screwdriver to punch each wire down onto the 40 pin female connector. The 4 wires on the end of the 44 pin cable are your power ones and are not needed (yet). After you get all 40 wires punched down, crimp it and then use a ohm meter to make sure that all the connections work.
Now the power connector. I couldnt find a floppy power connector so I took one off of my computer power supply (warning do so at your own risk). Wire 41 and 42 are 5v. I used wire 41 and crimped it to the red wire of the floppy connector. I then used a 3 wire crimp to crimp the floppy center 2 ground leads to the wire 43. After that, I used electrical tape to tape the 2 wires not used and to protect the 2 crimps I did.
Now the case modifications. You will need a Dremel tool. There is some metal shielding you need to cut along with quite a bit of plastic you need to cut. The cd-rom will fit above the motherboard. There are 2 posts on the lower case that need to be trimmed down to the height of the level of the edge of the lower case. The top will need most of the plastic cut off along with the metal tabs on the one side. Cut the plastic to about 3/4ths of the way towards the back of the player. Your gray end cap will have to be cut to accommodate the new cdrom drive too.
It looks almost like it is supposed to be in it! The color of the cdrom is just a little off from the gray caps but still looks kind of natural.
Like I said, give me a day or so to put up links for the pictures.