just bill them like i did
Under United States law (Under 47 U.S. Code 227) it is unlawful "to use any telephone facsimile machine, computer, or other device to send an unsolicited advertisement" to any "equipment which has the capacity (A) to transcribe text or images (or both) from an electronic signal received over a regular telephone line onto paper." The law allows individuals to sue the sender of such illegal "junk fax" or "junk email" for $500 per copy. Most states will permit such actions to be filed in Small Claims Court.
you may pay your $500 to email address via
www.paypal.com within 7 days.
regards hyper
if they dont pay take them to court and get a judgment