Here are the main big players in toy trains (starting from largest, to smallest)
Lionel, LLC
MTH (Mike's Train House for older trains)
Atlas/Atlas O
K-Line (accessories, frieght and passenger cars)
Bachmann/Bachmann Spectrum
LGB
Lego Trains.

I think this is either LGB, Bachmann or Bachmann Spectrum or possibly Marx. What is your feedback from Trains.com? And are you are a "guest" or user?