I've got 2 checks for an antique shotgun sitting on my desk.

One is a cashiers check, on a genuine check form but otherwise completely bogus from a "People's credit Union" in California that puts telephone callers on an endless hold. I'd guess a bunch of their blank checks were stolen.

One is a certified bank draft from the American Express Bank that is just a very well done copy. Even part of the watermark was reproduced but not the microprinting.

Both were from Nigerian scammers. They had sent the checks off to remailers in the USA long before they became aware that their scams had failed.

I did manage to trace one email back to Lagos Nigeria but most of them and the phone calls used a spoofing program to switch to a fake origin.