I was about to suggest something like this! Mine is specific to hiking though, and in reverse of what you're proposing. I'll add my input here but let me know if this belongs in its own thread (I'm new here).
When you search "___ trail" or "___ trailhead", would it be possible to show a map of the trailhead (with it pinned) and maybe a map of the trail itself? fs.usda.gov always has lat/long for trailheads in the location section, usually on the lower right. Example: http://1.usa.gov/1DGrpK1
In my area (Portland, Oregon) there is a wiki field guide (barely wiki though, it's difficult to get editing access) that has a decently standardized format: http://www.portlandhikersfieldguide.org/