Search for top-selling products by typing "top selling items" in eBay's search field, and then selecting a category from the pull-down menu next to the search field. Because eBay no longer provides a list of its top sellers, you must comb through the results to see if a seller has sold any items and, if so, how many. The results also list the number of bidders and watchers, additional indicators that the item may be popular.
