Modern Hagiography
Lives of the Saints by Alban Butler.
Our Birthday Bouquet Culled from the Shrines of the Saints and the Gardens of the Poets by Eleanor C. Donnelly.
Pictorial Half Hours with the Saints by Auguste François Lecanu.
Medieval Hagiography
The Cult of Saints in Late Antiquity Database
Gregory the Great, Dialogues (search for additional references)
Art & Architecture
Emblems of Saints by Which They Are Distinguished in Works of Art by F. C. Husenbeth.
Nihil sub sole novum 