The Library of Congress Red Book. It was intended to guide the Library of Congress librarians in classifying books. It turned out to be a deeply cross-connected network detailing the structure of human knowledge. Follow its links assembling a list of appropriate book catalog classifications. Then go to your library's Shelf List. It lists every book in the library as it is located on the shelf (that is by these classifications). It's better than browsing the shelves themselves because many books are checked out. Assemble a list of promising books and proceed to read and take notes.
1. Find some blogs. Toss them in your RSS feed. These will lead to other people with expertise.
2. Throw a lot of time and attention at what you find.