Some advice that helps me to hit my daily macros are eating protein rich in the morning, and load up on carbs mid day, and back to protein based meals for the after noon. I personally tend to get my fats in in the morning because I find it supports my eating habits.
Some staples for me are fat free cottage cheese and greek yugurt, chicken, cans of tuna, talapia (really cheap at wal-mart) and protein powder. I tend to eat these types of foods all day due to the abundance of protein and lack of, or low amounts of fat and carbs.
I've never tried P90X but I've been through the gruelling two months of Insanity and you won't have a lack of an appetite, I'll tell you that much!