To master distance control, putt up and down a “ladder”. Mark various distances, each one foot from the hole (so, mark distances at 1ft, 2 ft, 3 ft..and so on…) and putt up and down this line to practice putts of various lengths. You can do this uphill, downhill or sidehill.
Want to improve your putting this season? Check out The Fundamentals of Putting, as seen on The Golf Channel!
franklygolf 
Good advice. I usually do 3′, 6′, 12′ (or some more random version of that). In other words, Once I get a basic idea of green speed (~10 putts), I try to not hit any two putts from the same place.
I was at the LPGA event in San Francisco and spent a fair bit of time watching the ladies practice. Almost all (especially Ms. Wie) needed this distance sensitivity training.