Law libraries. You can find one near you, there are self-help type books for individuals as well as, usually, thick stacks of case law like you’re seeing in this photo. Although most of those stacks are now digital. I work in a university, and my office happens to be in the law library, which is also our county law library, so is open to the public. People do spend days and weeks researching and compiling paperwork. Some people also jerk off in the stairwells, because, public library. It’s boring and interesting at the same time.