I'm in the same boat that you are. Although I already picked my machine (MMR that I'm currently waiting on). Originally, I said that since we have techs here where I live, I'll just use them if I ever have issues. But that can get expensive very quickly if you don't know what you're doing, especially if it's something very minor. Your best bet is to just ask questions on the forum, watch YouTube videos, and follow the thread of whatever game you own. Many owners will be able to help you with the specifics.
Soldering looks scary as hell. I suggest you get a soldering iron and one of those little "kits" that can be purchased for under 10 dollars that allows you practice learning how to do it.
There's a book I've been reading:
http://www.amazon.com/s/ref=nb_sb_noss_2
It's a nice little guide to familiarize yourself with maintenance, but switches between electronic and EM machines continuously and feels like a textbook. If you're the type of person like myself, you'll only learn how to do something when you're actually forced to do it yourself.