Kage, you could try Bytelove. They do designs for ThePirateBay and a few other geeky website, plus some other geeky shirts etc. They're a little expensive but the shirts are very good quality - I've had my TPB ones for quite a while now and they're still in good condition.
Not sure how you go about 'hiring' them though, but: http://www.bytelove.com
Also, they're based in Sweden so how that'd work with American customers I don't know.





