AuctionMagic is a handy and powerful bidding/auction management software for eBay.
It will track you auctions and place your bids moments before the auctions close to greatly increase your chances of winning. AuctionMagic pioneered eBay software, with the original released back in 1998.
Use Bid Logic for selective bidding, bid on an auction only if it meets certain conditions, e.g. you win or lose a particular auction. With this method you can bid on similar items from different sellers until one wins.
15 day free trial for Windows 98, Me, 2000, XP, 2003, and Vista.