Like they have said, it actually all happens quite quickly, it doesn't usually take long once they get the IV up you. I remember being wheeled around with four nurses and the doc all poking and prodding me, tapping my wrists etc. I remember the doc saying he was about to put me under, and giving some corny reply like "alright then doc, ladies, take a load off my chest!".
I was out like a light after, woke up giggling on drugs and making jokes with some other patients in the recovery room. That part was a blast...We were all high and laughing about nothing. One nurse said I kept hitting on her with my eyes closed (I have no memory of that) but I remember those other people all feeling like my very best friends for about 15 minutes.
Oh, and when you wake up they usually have an electric heated blanket around you, it feels so comfy, especially while all looney on drugs...It's fun