I have run in to the same situation a couple of times on ebay. I recently sold an item, non Hl, seasonal Xmas item that the timing of selling at the first of DEC was critical to the final price. The high bidder after contacting 3 times finally replied and sent their address via email. I never received payment and they will no longer reply to my email. The next highest bidder has now purchased another item and I have lost the window of opportunity to sell this item this year. I had to pay the end of auction fees so I am not real happy. I did not leave them negative feedback due to the fact that I don't want to get negatives in retaliation. I feel it's better to live and let live, but it is still very inconsiderate for someone to do this.