Pinball Machine Care and Maintenance by Bernard Kamoroff.
This book was one of the first books I bought about pinball machines.
It's interesting, especially if you are interested in the older games (electro-mechanical and first generation electronic).
When you're interested in machines made after 1990, this book won't be useful.
At first sight the book may not look interesting. No glossy pictures, ball-eye shots of colorful playfields.. but that's not the goal of this book. Its goal is to provide answers to every question a new pinball machine owner will have.
As this was also the goal for me when I started this website, I found this book very interesting.
It answers all the basic questions one has, even up to the simple things like how to remove a glass, open a game, what types of light bulbs are used. What to do later, what maintenance is required, what basic repairs can one do, how do specific assemblies work, ..
Back when I started this book was a great source of knowledge. I didn't know anything about pinball machines and had to discover it all myself. Online there was also almost nothing to be found about these great machines. Nowadays I wouldn't recommend this book anymore. Buy it if you want to collect books and have them all. If your goal is to learn about pinball machines, there are many sites online that will teach you the same information.