My first ever mining history purchase was Hamilton-Jenkins Mines and Miners of Cornwall Pt. XVI. Wadebridge, Camelford and Bude. On a family holiday to Bude in 1974 it allowed me to go out and visit a few interesting sites, surface only, and switched my interest from looking for interesting minerals to investigating old mines. If you can get a copy, it will direct you to what sites are within easy range of Bude.
I still have the book, with its grey card cover, but it is in a pretty awful state now!
If you are into industrial remains in more general terms, don't forget the Bude Canal.