So this may or may not be a good idea, but if you really want us to find him I highly suggest posting whatever info you have on him, even if it "identifies" him (name, number).
GAF Detectives will find out where he works, lives, etc. in an hour. It's an extremely arduous process trying to explain to someone how to do that detective shit. We can't help you beyond extremely basic suggestions (which have all done nothing so far).