Hey Jamie, that's a great question, the one that really clicked for me was Ben Stoeger's stuff, especially his books like Dry-Fire Training and Skills and Drills. What made them great is they're not just a bunch of theory, he breaks down the "how to" and gives you actual, practical drills you can do to get better. It just made a ton of sense and gave me a clear path for practice. What kind of shooting are you trying to work on?