Here is a list of various link that you may find helpful for Art related products, Art sites and Art directory.
Online Art Gallery
Artchain.com
Artspan.com
Gallerytoday.com
Specializing in selling original paintings from USA and Europe.
Art-bridge.com
Art-Bridge.com Art Directory, Art Portal, Art Links dart.fine-art.com
artquest.com
Vladartgallery.com
Online Art Directory
You can find more art related sites in the following directories:
Dmoz.org:
The Art List- Monthly e-Newsletter and searchable database listing upcoming Art Contests, Art Competitions, and Opportunites for visual artists and photographers.