Yes, the steerer is measured from the "land" that the bearing race sits on just above the fork crown. The bearing race will be plated either chrome or black and will be the upper-most part of the fork that is below the headtube of the bike. (the headtube will include the lower cup at this point) The other end of the steerer is just below the headset lock nut (about1/8" or so under the nut end). Since the head tube bulges out a bit and makes it difficult to get an accurate measurement, I would bend a 12" piece of coat hanger wire into a "C" shape to use as a caliper of sorts to span the distance.

I will snap a pic a bit later and mark it up for a clearer description if no one else has.