Summon will usually be your best starting point for finding articles, books and other material on your subject. Watch a video introduction to Summon (6 mins) or see our collection of guides to making the most of Summon.
Art & Architecture Source is a major database of journal articles. Not all are in Summon, so it's worth searching separately.
Arts:Search is an important resource for fine and decorative art and design in the late nineteenth and early twentieth centuries.
Oxford Art Online is an excellent introduction to artists, schools and themes, in the fine arts in particular. It has several components, of which Grove Art Online and the Benezit Dictionary of Artists are often the most useful. They can be searched separately or together.
Sales catalogues guide: guide to finding sales catalogues, at SIA, at other libraries, and online.
Price databases guide: links and information.