common things you'll see the beasts on here eating are Skinless Chicken Breasts, Lean Beef, Fish, Canned tuna, turkey breast, cottage cheese, and eggs for protein sources. Whey's good, but I wouldn't recommend it as your primary means of getting protein.
Great sources of carbs would be oats, brown rice, and sweet potatoes or yams.
Around workout time(<45 minutes before,during,or right after), it's sometimes acceptable to get simpler carbohydrates into your system. I like to use gatorade or Waxy Maize starch.
Vegetables are also pretty important. spinach, broccoli, cauliflower, brussels sprouts (not as bad as everyone says they are, especially if you grill and season them), kale, bok choy, tomotoes, peppers, and red cabbage are all great choices to take. Dark or colorful vegetables tend to have a lot more important nutrients than lighter ones. Not only will these supply you with great micronutrients, but they help you poop.