Tank by Patrick Wright, but it's a bit dense, verbose and the reviews on Amazon are fill of idiots who don't get the concept of social history, and have issues with long sentences. But it's full of weird shit, like JFC Fuller's involvement with the Occult, and an Italian Fascist journalist's tours through Barbarossa with the Heer and in Italy with the Allies.
Also, get James Dunnigan's
How to Make War, (I've got a 1st edition somewhere, while the 4th edition apparently doesn't go as indepth about nuclear weapons.)
Meanwhile, as soon as I get money, or time to get to the library, I'm going to score copies of Joseph Maiolo's
Cry Havoc and get some stuff by Fuller, Tukhachevsky and others, since at some point it's just easier to get it from the horse's mouth.
Aside from that, just post a thread in npc, and stuff should just come out of the wood work.