Model Railroading

DJsTrains - Hobby Shop, Information, Tutorials
Model Railroad Academy
Railroad Signals of the U.S.
Railroads In America, U.S. History: Definition & Background
Spruce Crafts Model Trains
The XTrackCAD Wiki
Webville and Hypertext Railroad Company

Supplies

Athearn Trains
Kadee, The Coupler People
Model Train Stuff
RLD Hobbies
T and K Hobby
The Atlas Model Railroad Company
The C&E Branchline Railroad Shop Dunmore, PA
The Model Railroad Shop Piscataway, NJ
The Train Station Mountain Lakes, NJ
TrainWorld
Walthers