What are a few resources you would recommend to someone looking to gain insight into becoming a better leader at any level?

I hope everyone gets this. Standing under here and listening. Very informal, but extremely important, You would be amazed at the knowledge that is given under these limbs, some retained, most disregarded. When I was at Riley, they actually had posters up telling NCO's and Soldiers to go out there and talk and learn. They ACTUALLY did this. You would see Soldiers and NCO's on the hill under various tree's talking (some smoking and joking too), but they were there. Oak Tree counseling is an effective tool even in the civilian world (if they understood it's use), as a means to bring up subjects that are touchy, sketchy, and questionable, and get feedback that is honest and not humiliating. I think in the civilian world this would be seen as an "off site", and due to costs, wouldn't be implemented often.

S.L.L.S. Stop. Look. Listen. Smell. You can judge a lot about a person when you give them "power". See how that person is able to interact with his Soldiers. How he gets them to do what needs to be done. Sometimes that power causes people to forget where they came from. They forgot the day when they said " I will never be like that!". Look at the Leadership styles and figure out what fits you best. Adopt some, adapt some and learn what gets your subordinates attention. People appreciate the Leader that can personalize his styles to his Soldiers and still demand the same standard. It creates a professional relationship not a systematic chain of command.

LISTEN