The world's largest occult library has a public online archive

Amsterdam's Bibliotheca Philosophica Hermetica (AKA "The Ritman Library) houses more ths 25,000 occult texts, covering "Hermetics, Rosicrucians, Theosophy, alchemy, mysticism, Gnosis and Western Esotericism, Sufism, Kabbalah, Anthroposophy, Catharism, Freemasonry, Manichaeism, Judaica, the Grail, Esotericism, and comparative religion." Read the rest