There is a book titled "Butcher Bird: The Focke Wulf 190". I haven't looked at my copy in a LONG time but if I recall correctly it was a pretty nice book, not rare by any means but pretty well written.
It looks like there's one for sale on Abebooks and a couple on eBay. Mostly for around 50 USD. Not sure what your budget is but that doesn't seem too unreasonable.