Most if not all proper bodybuilders will eat 6-7 meals a day, all rich in protein.
I know Jay Cutler takes the usual Protein powder and creatine and some other products which will improve your liftin in the gym along with intra-workout products and products to boast testosterone
You only actually need to take protein powder once you've lifted, or you know you won't be getting your daily macros that day, buy your chicken and whatever else in bulk, eggs are cheap and has a lot of protein