Where to say in Tokyo with lots of nightlife/clubs??

[Glen]

I am young professional male. Was born in USA .This is the first time traveling alone.
I have been to many countries but never Japan.
My question is which area of Tokyo should I stay in?
 I want to basically have fun, go to night clubs, meet friendly people, Japanese and foreigners, etc. I just want a good nightlife city.
What about the night clubs and are they too much of expensive?
Any suggestions?