Get a mailbox in Detroit, order fish from Rapps to that address... drive over, pickup your fish, declare them at the border and bring 'em home? That's how we do it here in Fredericton Well to a border town just inside Maine as Detroit would be a long roadtrip
You could also probably arrange to pickup fish from Dan @ TNT Aquatics:
I agree with con-man-dan, I've gotten fish from cichlaholics.com as well and I'm very happy with the fish, plus Spencer is really good to deal with. I don't really know how the ordering them online works from him, since he lives in the same city as I do, I just picked my fish up directly from him. But I highly reccommend him.
The only problem with Spencer is his usual stock list. Very light on CA/SA cichlids. He did say that he was planning on expanding on that this summer/fall though! But if he's got what you want, go for it!