I'm going on a deployment soon and will not have access to google/internet in any way.
I want to start teaching myself some coding languages while gone, but I dont know where to start.
I'd like to learn some kind of game programming language and come up with a baseline RPG by time I come back.

What books, programs, and sources could help me do this?
Not sure what language I'd like to start with, but I'd really like to get into RPGish game development, is that helps.

Will I need a game engine?
What programs should I look into?
I don't want to just learn to code a game, but I'd like to learn, in-depth, what each part of a line of code represents and why it's organized the way it is.

you have two options. either you will spend hundreds of hours learning programming prior to making games, or you can mostly skip the programming and go straight to making games without it. if you're the latter, look into GameMaker or RPG Maker. there's a lot of drag/drop so you can focus on your creativity, but there's also flexibility so you can write scripts to go beyond that. if you're the former, then i suggest you get a solid programming foundation and forget about games for a year or so. you can learn something like python / c# / java.

there's a recent topic about making games that might interest you:

http://forums.d2jsp.org/topic.php?t=73407171&f=120

That's a good question. I just started learning as well and it's all been online so far, no books yet. I guess you would need to pack as many books/resources as possible? You can take a laptop with you yes? I hope someone more experience can help you here. Good luck to you and thank you for your service!

I am unsure to what you mean exactly hope i was a help.
Kernighan & Ritchie's The C Programming Language
It is a book that I find helpful in this situation sir. Good luck