Auction Bids

From wow.incgamers.com

Tracking your bids via the in-game auction system.

The second tab along the bottom is Bids which enables you to track items you have bid on allowing you to chart the auction progress for the duration of the auction. Once an auction expires the item is automatically removed from the list. Should you be outbid in an auction, you will receive notification of the outbid via the in-game mailbox (along with your money attached). If you are online, you will also see a message flash across your screen and chat log at the moment you get outbidded. If you are in the auction house while you get outbidded, the money is returned directly into your pocket and no in-game mail is sent so you can rebid immediately.

If you are outbid and wish to bid on the item again, you must travel back to the auction house to do so.