Ask HN: Professional/Leadership Development Without Buzzwords?

I've worked my way up the ranks from programmer to an executive level at my small sized company. I'm not brand new to managing people but all of my training is on-the-job. With my promotion, I've been asked to seek leadership training or professional development to help me become a better manager and a better leader.

What professional development, leadership courses, or even executive coaches have you used that you'd highly recommend?

Thanks!