Sounds like you're combining a couple of ideas there, and it might behoove you to read a couple of books focused to those areas.
Specifically:
Frugality
Investing
Retirement
(And potentially real estate, perhaps.)
I'd split it up and target the area you know least about and read up on that. Then, when you feel you know more about that than most of the areas, switch to another area, and read on that. (For example, you may feel you're pretty good with frugality as you are right now. Then skip it, for now.) Repeat until you have a handle on each of the specific areas of FIRE.
An catch all/"all-in-one" book may touch on each area quickly, but probably won't go in-depth enough on any one area to be as accurate and helpful as you need. It'd be a good resource for someone new to the concept, but not someone wanting to dig in further, like you seem to be.
Later on, when you get closer, you will want to add on Post-FIRE reading (but what will you
do all day?).
Nord's list will give you a good place to start on each of those:
http://the-military-guide.com/recommended-reading-books-research-papers-and-articles/