Here are some tips in case you would like to begin investigating the impact of a railway in your local area.
If there is no longer a railway in your vicinity, you can find out whether there was a historic railway by consulting the British Rail Pre-Grouping atlas and gazetteer (Ian Allan Publishing, 1997, ISBN 0711003203).
Once you have identified a railway you would like to investigate further, you can search Portcullis, the Parliamentary Archives catalogue to see whether any materials are held. Railways required an Act of Parliament in order to be constructed, and therefore plans and books of reference, which had to be deposited as part of the legislative process, are usually held.
Railway bills were often opposed, and therefore were often considered in detail by an Opposed Bill Committee. These committees heard evidence from local people, railway promoters and engineers and are a rich source for the history of the locality as well as of the railway itself.
You are likely to find much archive material of interest at the local archive covering the area of the railway. You can find contact details, opening hours and catalogue information at the ARCHON Directory, held by the National Archives.
There is also a useful guide to Railway records on the National Archives website.