If he is picking up via a western union, moneygram, or other instant money transfer agent, then he can be anywhere in the world.
You can try to find out his approximate location by using the headers of any email he has sent you.
If you don't know how to find headers, follow the advice on this website -
http://mail.google.com/support/bin/answ ... wer=22454#
When they appear, you should copy the lot and paste them in this website -
http://headertool.apelord.com/headers.
If the scammer is using gmail, hushmail, or fastmail, then this technique won't work. Also, if you choose to post the header here, please delete all your details from it - your email address will be in there a few times.
Another thing to note is that if no money has changed hands, then there has been no fraud and the police can't legally do anything.