Hey folks, just chiming in here. I kegged my first (that's right--Number One) beer and it was a hefeweizen. Took me awhile when I realized that the 'stock' line I had was 4' long that that's why I was pouring a lot of foam although the beer wasn't really carbonated. Then I was passed some interesting reading for my SECOND keg.
It is very in depth but as I've learned as a new-to-kegging person--read before you pour. I also started second time around with a roll of 10'. I didn't have the patience to start with the full 10' and cut back until I got where I needed to be (for THAT beer's CO2 vols, THAT temperature, etc) so I did calculations. And did them again.
Distance from center of keg to tap. Check.
Temperature of the beer. Check.
Diameter of the serving hosing. Check.
Desired CO2 volumes. Check.
Oh hey look at that. LOVING my pour at full-open with picture-perfect head and carbonation is just right. (for THIS beer style)
(for the record, I ended up at just over 5' of hosing 3/16")