There is a very interesting new site called Bid Nearby which is a mashup, or combination, of eBay and Craig’s List auctions overlaid onto a Google map in a given area.
Simply go enter the item you’re looking for and the site will display a map showing clickable pins which pop up descriptions of the items for sale at each location.
You could use this service to help cut down on shipping costs by purchasing items that are local enough to drive over and take delivery.