Links (provided for educational purposes only)

 Wikipedia - Quickly becoming one of the best encylopedic resources

The Cult Education Forum - Helps to sort out the wheat from the chaff

MetaReligion - One of the largest collections of religious and esoteric texts available

Internet Sacred Text Archive - Another large collection of religious texts

Digital Library and Museum of Buddhist Studies - Largest collection of Buddhist scripture and study material online

Shinto & Buddhist Corner - The face of Buddhism and Shintoism in Japanese art

Dao House - Links to Daoist (Taoist) sources

The Carmelite Library - One of Australia's largest collections of spiritual and mystical books

Hermetic Virtual Library - Collection of Hermetic texts

The Hermetic Library - A collection of Neo-Hermetic texts

Grand Lodge of British Columbia - By far the best source of Masonic information on the internet

Freemasonry Today - Magazine edited by Michael Baigent; author of Holy Blood, Holy Grail
 
Salto Al Infinito - A Spanish site that contains some very interesting articles on esoteric traditions and practices
(translated link here)