These are some of the railroad links that I spend some time on.  I am currently a member of the B&O RR Museum and the B&O Historical Society.

B&O Museum  http://www.borail.org/

  B&O Railroad Historical Society http://www.borhs.org/

  Western Maryland Historical Society 

  B&O Old Main Line  http://www.trainweb.org/oldmainline/