Just wondering if there is a book devoted to the Order itself, its politics, current famous figures etc as the internal politics of the order is my favored part of the game (too much vampire maybe...)
If no dedicated book, any suggestions on other books, beyond the Houses of Hermes line?
The three HOH books have a lot of what you're asking for, but each (natch) is House-based, not Order-based. But there's a lot there. You'd have to read all 12 chapter intros, w/ the History/Current status of each House, and then synthesize an overview from that.
I think there's room for something on the Order as a whole. It would mesh in the the books mentioned above but be 90% new material. It would cover changes over time, tribunal meetings, inter-tribunal politics and all the other good stuff mentioned above.
Mind you, I've bought everything for 5th edition except Calebais (already played it) and Fallen Fane (I'm not into LARP but perhaps not getting it was a mistake anyway).