Seconded on the DVD player batter. Another name is "RB-270". Somewhere here there is a thread with a ton of different names. Some DVD batteries are 7.5V, most are 9V, and you want 9V.
Generally, they come with a cable, and adapter tips. The problem is that Edirol wires things up backwards with respect to the rest of the world (Edirol has positive on the outside), so you'll need to cut the cable in the middle, and solder it back together with red-black mixed. R44, R4, and UA-5 all the same in this regard.
Or, if you don't solder, go to Radio Shack and get the "Adapt-a-plug" kit with a cable and a "B" tip and an "M" tip, for the overpriced amount of about $20. Plug one tip on (+) and the other tip on (-). It doesn't matter which is plus and which is minus, just so long as they aren't both the same.