Artfact
Art, antiques, collectibles: over $80 billion in auction prices; reference info. find now at auction: over 500,000 artists & over $80 billion in antiques & collectibles
http://www.artfact.com/index.cfm
Artprice
Artprice.com, the world leader in art market information : art price guide and art market reference book, art market confidence index, art marketplace, updated world auction sales calendar, art prices, artists records at auction for painting, drawing, prints, sculpture, photography, tapestry, miniature. indices. antiques. artists' biographies.
http://www.artprice.com/
D'Art fine-art
D'Art fine-art
http://dart.fine-art.com/
Gordons
Gordons
http://www.gordonsart.com/