There's a lot of books on railway stations. Here you find a selection I took from the site of Barnes and Noble. You can click on the links to know more about the books.

The Modern Station: New Approaches to Railway Architecture	Railway Stations
All Stations to Murder: True Tales of Crime on the Railway	Cities on Rails: The Redevelopment of Railway Station Areas
The Directory of Railway Stations	Railway Heritage: Paddington Station
Railway Station	Railway Stations of Britain: Just a Glimpse
Southern Railway Depots, Vol. 2	Southern Railway Depots: North Carolina, Vol. 1
Train Doesn't Stop Here Any More: An Illustrated History of Railway Stations in Canada	Waldo at Railway Station
Railroad Stations Depots and Roundhouses	Grand Central: Gateway to a Million Lives
New York Central Stations and Terminals	Railroad Stations
The American Train Depot and Roundhouse	Grand Central Terminal: Warren and Wetmore
The Railroad Station: An Architectural History	Living in the Depot: The Two-Story Railroad Station
Train Leaves the Station	Thousand Voices: The Story of Nashville's Union Station
Worcester's Union Station: The Monument and the Memories