One caveat - I have sold a few things where the person who was the buyer had really insane spam filters, or worse, the Earthlink software where I had to "pass" in order for my email to be forwarded.

Just recently someone ordered an item from my, and sent increasingly vile and threatening emails when he "didn't hear back from me", you know, he'd have Mr. Visa, Mr. Mastercard, Mr. Cops and Uncle Sam on my tail.

Actually, I'd already sent him four emails trying to reach him. I finally had to leave a message on his voice mail - at which point he discovered that there were indeed, many emails from the past two weeks sitting in his spam filter.

Assuming that isn't the case...

Get a copy of the emails - including the headers - and then go onto one of the Discussion Boards for more help with that, try the Feedback forum first. They can help you find the best place for that and better yet, you'll help warn other people in the community.

With something that cut and dry - you've got his emails trying to negotiate after the fact - he will get in mucho problems with eBay.