Chris,
Do a search on the Surveyor forum for TransDem and/or baseboard. TransDem is a pay program (about $30 bucks) and has a bit of a learning curve but is well worth the money if you really want to do a prototypical route.
Also, there is a scenery item on the download station called Square A 1km, or something like that. The idea here is to take a 1km X 1km map square from Google Earth or similar map program, save it as a 1024x1024 image and paste it onto the Square A scenery item (first, open it for edit in CM and then access it with your favorite paint program from Auran/TRS2010/User Data/Edit--there is a tutorial of sorts, just do a search for 'baseboard').
Go back into CM, commit it, then you select it in Surveyor, position it over a baseboard and lower it just below the surface. Turn on the wire-frame view and use the Square A map as a template to place your track, buildings, roads, etc. You can reuse Square A as many times as you want and just rename it before saving.
Hope this helps.
