Here's a discovery: a website that bills itself as An A-Z Guide to British and Irish Railways on Film.

It tells you where the railway scenes in each film were shot, has plenty of screen captures and appears to be reasonably comprehensive.

In effect, it's an online version of Horton's Guide to British Railways in Feature Films, which I keep by me when watching Talking Pictures TV.

The image above (borrowed from another site) comes from the minor Ealing comedy The Magnet (1950). It shows Stephen Murray (the great uncle of Al Murray) and a very young James Fox on the platform of a station on the Liverpool Overhead Railway. The A-Z Guide suggests it is Canada Dock.