Tzimisce.net - Information on the Tzimisce clan, complete list of merits and flaws, character creation information and much more.
Gnawed.org - Malkavian resource page, includes derangements, tips on playing a Malkavian
Fataladdiction - Parent site of this page, and has information for playing and creating ghoul characters.
Diablerie - Roleplaying via IRC. Contains information on how to get started on Diablerie and rules.
White Wolf - Publishers of Vampire the Masquerade