Here are a few resources I've enjoyed so far on my week-long planning/strategy sabbatical. Some are new to me. Some are for review or rereading or re-listening. Some books I'm reading in full, some in part.
Tim Keller: Should I Not Love That Great City?
Tim Keller: The Meaning of the City
Tim Keller: Love for the City
Tim Keller: Why to Plant Churches
Mark Driscoll: Leadership Lessons from Nehemiah Part 1, Part 2 (notes Part 1, Part 2)
Philip Yancey: Prayer
Bill Sullivan: Ten Steps to Breaking the 200 Barrier
Bil Cornelius: Go Big
Bill Hybels: Just Walk Across the Room
Church Leader Insights (Nelson Searcy): Momentum and Church Growth (post/article by Scott Whitaker)
I'm also doing some of my planning/strategy work at Bubbl.us, which is a simple way to do mind-mapping.