Are you a "hardgainer"? Do you lift and lift yet you still don't see the magical fruits of your labor, like increased muscle size and strength?
Well, do you eat like enough to make these gains or do you eat like a 12 year old anorexic girl and have a crouton and a glass of water at dinner to keep your precious six pack? If you do eat food on a regular basis, do you eat the right kinds? How about at the right times of the day and in the right quantities and ratios of macronutrients?
Seriously, I'm not gonna be one of those guys who says that nutrition is 80% or even 70% of your total muscle gains, but it is a huge part. I used to think I ate enough food yet the scale never tipped. However, one day I started using Fitday.com.
Boy, was I totally wrong. I wasn'y getting nearly enough nutrients for my needs. This site has it all: vitamin and mineral breakdowns, percentages of your calorie intake and where they come from, and they even have an option to make a new food entry if the one you want isn't already in their database. The greatest part is that it's free! If you are serious about your gains and nutrition, I highly recommend using it.
Also, you might want to checkout Dr. John Berardi's book Scrawny to Brawny.
It has all the information on nutrient timing, ratios, and when and why to eat, and it even has some good recipes in it. The beginning also has a pretty good workout scheme that goes right along with the premises of the book. Give it a look and see if it can't help you, unless you like being constantly mistaken for sapling.