yes radio shack sells them but at 30$+ tax I would be better off buying a new router.
There should be a diagram somewhere, either in the manual or on the unit itself
In most cases its right above the power input on the device. this one doesnt have the diagram and I dont have the manual as I got it for 5$ off ebay. Most devices are the same polarity, the only things I can think of off the top of my head that are backwards are the sega genesis and an old keyboard I have
anyway I just want this thing to play my psp on. so if anyone has an adapter that may work or just an old wireless router they dont need anymore, just let me know and we can work out a trade.
p.s. when your looking at adapters the output should be listed as 4.5 v 1.5 A or it may be listed as 1500 mA. Im guessing there are probly some cordless phone bases that work off similar specs.