This is a fantastic book. Buy it if you haven't already. Fantastic book. Really, one of the best books written in any field. Written by Arnold Schwarzenegger. Highly recommended.

http://www.amazon.com/The-New-Encyclopedia-Modern-Bodybuildi...

I'm excited for you. You're embarking on a great journey, you don't even know! Or maybe you do. :)

Dont underestimate the diet. You can waste a lot of Gym Time & Effort by having a shit diet. That time and effort lifting things will be 1/2 as valueable if you dont eat properly.

You dont have to go Dwayne Johnson on it, but eat a little cleaner, get a lot more protein, dont be worried to put on a little pudge (if you're a skinny kid). You can quickly lose the fat, but the muscles are impossible to gain without the food.