As we wait for Security, Territory and Population (“published 3 April 2007″ does not necessarily mean it is available for delivery!) we should note that there are at least two (legal) samples of the book available online.
Selections from the same lecture have also been published in Political Geography as “Spaces of Security: the Example of the Town” (pdf). This does not include the whole lecture, but this issue of the journal contains some interesting secondary literature.
Both were translated by Graham Burchell who is now doing all the translations of the Lectures. Of course most people know about the “Governmentality” lecture (1 Feb. 1978) published in The Foucault Effect, but this was from a rather indirect source.