This netbook details the British answer to the Initiative. It was written by Paul Leone and is, in my opinion, a must read. Even if you're not running a "canon" style Buffy and Angel game, the two organizations detailed herein are more than suitable for any supernatural action or horror game.
This sourcebook for the Buffyverse contains details and sample characters for two paranormal intelligence organizations: S.T.R.I.K.E. (Special Tactical Response for Interdimensional Key Emergencies) and Military Intelligence Group 7 Limbo Unit a.k.a. T.R.A.N.C.E. (Transdimensional Research and New Cosmos Exploration)