A Nocturne for the World of Darkness: Features rules and background for Setites and Toreadors in Vampire: The Masquerade and Vampire: The Dark Ages.
A Short Introduction to Vampire the Dark Ages: If you're interested in trying Whitewolfs Vampire the Dark Ages roleplaying game, this site gives a nice snappy one page introduction.
Clanbook Lhiannan: A resource for clan Lhiannan. Features information an introduction, character sheet and history.
Koldunic Sorcery: About the ways of sorcery of the Tzimisce Kolduns, written by Ronald Romine and based on Slavic folk beliefs.
Malio's Vampire: The Dark Ages: Character statistics.
The Whitewolf Vampire Chronology: Gives a quick but well rounded chronological introduction to the history of vampires for Whitewolf's Vampire the roleplaying game.
Vampire History: A collection of writings on the Dark Ages clans.
Vampire the Dark Ages Home page: White Wolf's official Vampire: The Dark Ages site. Contains product information, FAQs, signature characters, Dark Ages forum, and character sheets.