Hiya —

1. There are books that are history of the history profession (e.g. Novick's That Noble Dream), but none that I know of that focus on their couture. One particular favorite article of mine on the history of the profession is Bonnie Smith, "Gender and the Practices of Scientific History: The Seminar and Archival Research in the Nineteenth Century," American Historical Review 100, no. 4 (October 1995).

2. When I was a student historiography was basically an honors class for history majors, to be taken in the final semester of the senior year, but when I was in grad school the professors tried to teach it to sophomores. There are pros and cons to either of the approaches in my view (I think it is a little hard to get sophomores interested in historiography, personally, if they don't yet know much history; I don't think reading a lot of historiography makes better historians, either; but such are my views, others do not always agree). Anyway, I am not quite sure what you are asking here. Historiography is a useful way to see outside of your own biases and blinders — it de-naturalizes the work of the historian by showing it to have its own historical context and flow, and that does let one think differently about one's own practice.

3. I have honestly never found a useful guide for writing history. I have found Hayden White's Metahistory a useful way of thinking about the purpose and work that narrative does, for whatever that is worth.

4. If you haven't read James Ellroy's American Tabloid — lucky lucky you! It is an entirely fictional, conspiratorial account, but it is great fun — he synthesizes every conspiracy you can imagine into one thick, violent, neo-noir soup. It should absolutely not influence your historical thinking at all. But it's a great read.