So you want to have a power adapter that goes into the wall right? Assuming you want to cut into the cord, just get a 12V Wall wart capable of supplying the needed current. Or use a 5V one, which would probably be cheaper (since these things are abundant ).
If you dont want to cut into the cord, buy a female (the one that plugs into that one..lol) and cut one end off. The 2 leads you are concered about is the Black (-) and Red(+). I wouldnt worry about the other 2, unless the thing comes with software to control it O.o
5VDC/4A
$8.49
http://bgmicro.com/prodinfo.asp?sid=...cri=5v&stype=3
5V/3A
$4.95
http://bgmicro.com/prodinfo.asp?sid=...cri=5v&stype=3
EDIT-ok now Im done, you may read and reply