Here's something I learned recently. The consumption of fat means more testesterone. Of course that leads to more muscles.
Just try to keep it clean and don't eat a lot of carbs (especially high GI carbs), eata lot of healthy oils (olive oi, sesame oil, coconut oil/milk), moderate "bad" fats (cheese, eggs, beef), and of course protein.
Lift low and heavy (low repititions 4-6 reps, and 80 to 85% of your one rep max).
Weight gainer = your bodyweight * 15 + 500. (Ex: 160*15+500=2900) Eat at least (answer of) bw*15+500 calories.
NO2 is just a mental thing IMO.
Oh, and if you can get and read this book:
http://www.bodybuilding.com/store/bookeme.html
I know it looks like it's for wannabe juicers, this dude's stuff works no matter who you are!