LIMC: Lexicon Iconographicum Mythologiae Classicae. Art Reference [N7760 .L485] A key resource for researching the subject matter or iconography of ancient art. Multivolume, with plate and text volumes, entries are in a number of foreign languages, depending on the author. Even for those who do not read the language it is essential for its plates and bibliographies.

Dictionary of Ancient Dieties (Art Reference)

Dictionary of Pictorial Subjects from Classical Literature: a Guide to their Identification in Works of Art (Art Reference)

Dictionary of Classical Mythology, Symbols, Attributes and Associations (Davis Reference)

Gods and Heroes in Art (Art Reference)

Gods and Heroes of Classical Antiquity (Art Reference)

Oxford Guide to Classical Mythology in the Arts (Art Reference) This covers art from 1300 A.D. and later, but may still be of interest for art or literature majors.

Athena: Classical Mythology on CD-ROM (Davis Reference)