This is an educated guess. I'm a native of the region.
The SPV railroad atlas for Virginia, the Appalachia & Piedmont volume, lists the Hampton & Langley Field under the heading of short lines for which insufficient information is available to plot them. The description is that it operated 1927-1943 and was a common carrier for freight and carried streetcars for passengers.
A Chesapeake & Ohio spur ran roughly east-west from the main track in Newport News at Old Point Junction to Fort Monroe and Old Point Comfort. That spur now ends at the Hampton River. Old road maps of the Hampton-Newport News area show another spur running north from that one that paralleled King Street North (Va. route 278) into Langley Field. A system of tracks continued inside the facility (now Air Force). King Street North goes to the Langley main gate. An Esso map from the late 1950s clearly shows this spur, as do a couple of maps from the 1960s, but it is long gone today. Today's maps show no tracks remaining inside Langley Air Force Base.
My guess is that this old north-south spur might have been the H&LF, or at least part of it. The SPV atlas does not show this old spur to Langley at all. The Esso map shows that the area had far fewer roads and was virtually desolate by comparison with today's sprawl, and looking over the roads in existence then does not reveal any likely paths for abandoned rights-of-way (dead-end roads, etc.). Langley has a lot of water around it, and King Street North and the former spur actually bridged a tidal river on the approach into the base. This suggests that other paths for a track would seem unlikely.
Hampton is a sprawling city now, but it was formed from mergers including Elizabeth City county in the 1950s. The original town of Hampton is at the south end of King Street, just south of the east-west C&O spur that still exists. The H&LF might well have continued south at one time, crossing the C&O spur instead of ending at it, to provide streetcar service to the original town a few blocks further south.
This is just a load of conjecture, but I hope it helps someone. I'll keep looking out for old Hampton maps that might clarify this.
Edit: looks as if my conjecture is correct. This post says the H&LF was an electric line that ran from the C&O spur to the base where I thought it was:
http://www.railroadforums.com/forum/sho ... hp?t=10403