Most major galleries and museums provide searchable access to catalogues and databases of their collections. Search for the title of the gallery or museum and look for links to their catalogues/databases.
"Heir to the century of the Enlightenment and the French Revolution, the Louvre was quickly accepted as the "museum among museums;" and since then it has remained a model and a recognized authority. Founded in 1793 as a museum for all, it celebrates humanity's long journey with the remarkable scope of a collection that spans thousands of years."
