Here are some links to other sites I think are worth a visit:
End of the Line - Ian Furness
Foto Rail - Kevin Smith
The Iron Road - Scott Borthwick
Matt Spencer's Railway Photography
Monkeysnaps3 - Bill Watson
Rail Net - Marcus Dawson
Railway and Freelance Photography By Jonathan McGurk
Railway and travel photographs by Paul Bigland
Trains Are Hell - Martin Taylor
Here are some other websites that I find useful: