I got this cheap washbirn bass with 1 P and 1 J style pickup. I need a wiring diagram for this kind of set up so I can fix th FUBAR that someone did to it. Its got one volume pot, one tone pot and a 3 way selctor switch. Thanks.
try searching online. i think your chances of someone here having one is very slim lol. google it dude GOOGLE IT!!!
If you need wiring stuff try posting in the Guitar Building & Customising Forum in future but here:

Butchered from Seymour Duncan (cheers easy). The wires may not be the same colour as your bass but white = hot 'out' from pickup and black = ground from pickup. The 3 way could be:

left = P
middle = P+J
right = J

on/off/on (not recommended and probably isn't)
left = P
middle = nothing!
right = J

hth - and remember GB&C forum is better for the techie questions (they've even got an ultimate thread for this kind of thing).