Post all communications with buyer, removing personally identifying information for both parties. Send the buyer a link to this thread via IM and e-mail. Sit back, and a Mod will be along shortly.
ETA: Perhaps changing the titles of your two threads would be helpful in distinguishing which belongs to whom
Please Post all comms and IM and email him a link to this thread.
Also please change the title to "-1 for smsifford "