So many factors. Style is pertinent. A NY style pie uses less dough than (most) American for a given size(diameter).
Usually, if you use the formulas discussed within these forums(and learn to use the dough calculators), it's all given.
And as mentioned, it's still to your preference. I like American style, but I still prefer to use a little more dough(for a slghtly thicker crust) than many of the American style formulas.
So basically once you find a formula you like, then you will know exactly how much dough to use.