AskArt – The best place to find out about an American artist. Search by artist name.
ArtPrice – This is a great place to go if you have any type of art to research, whether it be a painting, print or sculpture. Just type the artist name into the search field. They give you any auction records, current pricing estimates and sometimes much more information including signatures, images or a biography. You get more information the more well known the artist is. Some features and information are available for free, but you need to pay a fee to get auction prices and more detailed information. If you have a piece of art you think may be worth something, the small fee ($8.25) is certainly worth it.
Absolute Arts – Database of contemporary artists.