Paul and Pista: Your best bet is Paypal, just put in a dispute saying you didn't get your stuff, and if the seller can't prove to paypal within 7 days he sent it, you'll get your money back.

I actually called the credit card company first and they contacted PayPal, who in turn contacted me. So I should be in good shape there.

Shants - have you tried calling recently? What time of day did you call? I've tried calling a bunch of times and they haven't answered in the last two weeks or so. I feel a little bad about cancelling the payment because they were so helpful on the phone, but now I can't even get in touch with them.