If you are a serious wine collector, you need to be aware of what happens at wine auctions. Not only will you get a sense of what your bottles are worth, you may be able to pick up cases of less-famous bottles you particularly like without taking out a second mortgage on your house.

Buying older wines from auction houses is always the best course, as these institutions have experts who have verified that the wines up for auction are authentic and were stored properly. The most reputable wine auction authorities in the United States are Hart Davis Hart of Chicago and Sotheby's and Christie's of London, each with major operations in New York City.

If you attend a wine auction, expect to pay a buyer's premium of 10 to 15 percent of your bid. One way to avoid spending yourself into a hole when the bidding gets fierce is to obtain the catalog ahead of time, identify the wines you want, and set bidding limits for yourself. Of course, this is easier said than done, especially if the auction is benefiting a worthwhile organization that will put your money to good use.