One of the best ways to gain knowledge is to read. Here are a bunch of books, websites, blogs and audio resources that you can check out. These will help you become a better strength coach, trainer and a better exerciser.
Advances in Functional Training – Mike Boyle
Easy Strength – Dan John
Goals – Brian Tracey
Anatomy Trains – Thomas Myers
Duct Tape Marketing – John Jantsch
The Power of Habit – Charles Duhigg