I'm not sure what your goal is. But my advice is to stay away from the major supplements like HGH. My nutritionist thinks of it this way...
Food always comes first: So this would be like your diet obviously. Eating healthy's more important than anything. If you train regularly try to keep your protein powders as a normal part of your diet. (i do three meals a day, plus 3 protein shakes = six meals

)
THEN
Supplements: The only one i use would be Glutamine. Its great also if you train regularly. It helps your muscles regenerate much faster and you feel more energetic.
But my goals may be different from yours. My goals just to train and work out and gain size slower but more naturally. i just think its a healthier way to go than bulking up extremely fast.