Artcyclopedia: the Fine Arts Search Engine
Criterion for inclusion is that the artist must be included in an arts
museum collection somewhere in the world. One can perform searches by
artists' name, the title of a work of art, or an art museum. Best part
of the site is the ability to browse through entries by name, subject,
nationality, and so on.
Link to resource:
Artcyclopedia: the Fine Arts Search Engine