It depends on both the quantity and quality of the practice you do.I bought my guitar(since this is when I consider myself to have really started playing,although I learnt my first chord way back)in 2000,and although I can play some stuff that impresses some people,I'm sure there are people who got to my level in a lot less time.
It's all upto you.
And since it seems you're looking for a teacher,make sure you get competent instruction.Be sure about it,just like you'd want to be sure about the amp you get for your guitar.
It's important.