Hi .. Ebay keeps all member's IDs private during the bidding process. Only seller can see and you can see your own but not other bidders..
"To keep certain info private, we limit how bid history information is displayed. When the highest bid, reserve price, or Buy It Now price reaches or exceeds a certain level, members can't view or search for member-specific information, such as user IDs, on the Bid History page. Though the Bid History: Details page has information on bidders, each bidder is assigned an anonymous name (x***y, for example). Only the seller can see a bidder's user ID."
Perhaps this link will help..
http://pages.ebay.ca/help/buy/aboutbidding.html