North American Transportation Atlas Data (NORTAD)
   Published by the US Bureau of Transportation Statistics. Provides geospatial databases of airports, highways, railroads and political boundaries.
   http://www.bts.gov/publications/north_american_transportation_atlas_data/

Omnitrax
   Information on the largest, privately held, rail services company in North America. Offers employment opportunities and contacts, a corporate overview and details of services to clients in industrial and transportation sectors.
   http://www.omnitrax.com/