So I know it is only the second link when you Google ‘abandoned photography’, but I want to greatly encourage you to look though this gallery of photography:
Tom Kirsch’s work dates back many years and he has an extensive variety of locations (honestly, find his ‘genre’ list and see). Sometimes I will see his work uncredited on Tumblr and I get upset. Frankly, this is a huge, legally photographed, beautiful collection of abandoned building photographs.
I highly suggest it if you are not already familiar.