There are plenty of those around and there is not much you can do. First thing first, put him on your blocked list. Then call ebay and explain the situation and say that you want to report the buyer. Ebay will say that they will refer the buyer to the Safety department.

But you will still have to solve your current problem yourself, ebay won't intervene.

I ususally go tough on these sort of buyers. You will get a neg, pretty much guaranteed, so why be nice?