Email them and explain a few things that I'm sure newbies don't know.
When a buyer bids on eBay it is a legal and binding contract that they agreed to when they bid.
When they bid, you incurred fee's from eBay and those must be recouped.
In order for you to recoupe those things you will have to file NPB (non paying bidder dispute) after 10 days with no payment. And will follow with FVF (final value fee's) to receive those fee's.
Alot of buyers don't realize that we as sellers pay fee's. Especially newbies. They believe since they are buying for no fee's and paying us via Paypal that has no fee's to them..that there aren't any fee's.
I've had several buyers that once they found out that I incurred fee's due to their not well thought out bidding, gladly offered to pay my fee's and drop the whole thing or just said, kiss my rear end and file for your fee's.
But it's in your best interest in the long run to first block, email and then file for NPB on the given day. eBay gives them a chance to explain their side when the NPB is filed and if they don't respond within a certain number of days, it's an even blacker mark.
NPB should be taken off eBay and with three NPB strikes against them they will lose bidding priviledges.
Good Luck,
Donna