Libraries. I love them. They are full of people who know their way around books, and not just books on the shelves of their libraries, but books from all over the world. If you are looking for books as part of your research always talk to your local library.
Here in Derbyshire, our local library also offers an amazing wealth of material on line. I have been able to consult the Oxford Dictionary of National Biography and newspaper archives courtesy of my local library service, without leaving my desk.