I do not recall where I came across this organization, but it was a railroad related web site/message forum.
The Society for Industrial Archeology can be contacted at:
Department of Social Sciences, Michigan Technological University, 1400 Townsend Drive, Houston, MI 49931-1295.
I believe the web site is:
sia@mtu.edu
I do not recall what the dues are, but anyone can join.
I just received my second issue of the society's newsletter. Cool stuff!
The articles cover canals, dry dooks, the steel mills in the Youngstown, Ohio, area, waterworks, shipyards, LOTS of bridges, power plant for a lumber company, a preserved O-4-0ST, coke ovens and installing a pre-fab turnout.
Lots of other interesting information, not necessarily relating to railroads directly, but certainly lots of industries served by railroads.
I strongly suggest looking into joining this organization, which is very railroad friendly, as a great source of information.