Phony buyers on Audiogon

Here's the story:
I'm selling an amp and I get an offer from a non-member to buy it at my asking price. No questions about the amp whatsoever.
While I'm a little suspicious what can I do? So I send him my name and address. Never get a check so send him an e-mail. He has no money and can't buy the amp.
Why would someone offer to buy and want my name and address when they don't intend to? Should I be worried?