Here is a list of various link that you may find helpful for Art related products, Art sites and Art directory.
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
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.
HotvsNot.com: Directory organized by subject, including Painting
DirectoryVault.com: DirectoryVault including Painting
Linknom.com: Link Nom including Painting
Directory.r-tt.com: r-tt Directory including Painting
Visit a search engines: