It's no wonder. The details available in places like Wikipedia on these bureaucracies are fairly sparse and abstract. (Which is surprising, since there are a few books on the subject, which I haven't read.) Where folks do talk openly about their time in such places, they might focus on juicy gossip about their co-workers, scandals, and major events, rather than on how the organizations actually operate—and how folks should use these systems to their advantage, from both within and without.
There are some pretty good reasons for much of this, as will hopefully become apparent. There are many incentives to keep information hidden, not all nefarious. Luckily, since I don't work at either place anymore, I can say (almost) whatever I please.
So, as an occasional series, I'll try to fill in some gaps. I'll start off with the State Department, as it's better-known and more fresh in my mind. If you have any questions to start off, please ask!