A dictionary of Christian Art. Murray, Peter, 1920-1992. New York : Oxford University Press, 2001, c1996.Lilly Library N7830 .M87 2001
Church, monastery, cathedral: an illustrated guide to Christian symbolism. Whone, Herbert.
Longmead, Shaftesbury, Dorset : Element Books, c1990. Divinity School Library Reference BV150 .W445 1990 c.1
Catholic Encyclopedia - 1911 edition online - A pre-Vatican II vision of the world. Great for saints and Roman Catholic theology. Written by devout Catholics at the turn of the twentieth century, an excellent way to get a feel of the topic.
Kaftal, George. Iconography of the saints in the paintings of [region] Italy. Florence, Italy : Casa Editrice le Lettere, 1985. Lilly Reference N8080 .K255 1985
Hagiographies are old-style saints dictionaries, usually organized by saint's days or ritual. A powerful glimpse into the organization of a mystical religious lexicography.
Lives of the Saints (Hathi Trust online)
The lives of the saints. Baring-Gould, S. (Sabine), 1834-1924. Edinburgh, J. Grant, 1914. Divinity School and Lilly Library Reference BX4655 .B3 1914