How do I find a drug dealer?

I'm on a drug hunt and plan to go to the city (Manhattan) to find some good ****. Is it as easy as it is in movies? Just look for the suspicious man in the tread coat at the end off the alley? I don't wanna get raped. Are city dealers more subtle nowadays? If I'm walking around will one eventually ask me if I need anything? Is there an easy way to find one? Please help my dealer only sells weed!