Wow do NOT, I repeat do NOT stick a needle in your dick. That's crazy. There is no medical evidence that suggests that GH will work on your penis, and it's just too risky to try. Hanging a dumbbell from your penis is also a bad idea. If you read about people doing this, yeah they do get a larger penis along with horrible disfiguration in their shaft and tip. If this is a real problem for you, you should visit a doctor or Urologist. Chances are your penis size is just fine though and you just WANT more...greed.
90% of men who use a penis stretcher are within the average range or higher. Why is it that men want an abnormally large penis? Bragging rights?! Anything bigger than 7 inches starts to hurt a woman, and some get scared off by such size.
Play it safe if you are going to try anything on your penis but first ask yourself: do I really need to do this?!