How soon?

as far as just performing oral sex, if I liked him and he knew I'd expect him to go it good, I'd probably let him by the 3rd or 4th date. however, I'd make sure it wasn't some ploy of his just to get me to do stuff to him or have sex. he would have to really want to perform oral sex on me.

Usually I let the guy do oral on me the first time we have sex. This has gone from first night we met up to maybe a month after meeting. Very very seldom on the first night however!
It depends on how I feel about the guy. There have been an occasional time where I have been really turned on by someone I just met and we end up having sex.

about six months but most likely a year cause one it would be my first time and two this is just the way that I am!

usually it depends how much I like him and if I feel that he knows what to do

mm I would say probably after a month