Startup Playbook by Sam Altman http://www.amazon.com/dp/B0181ZPASC/ref=cm_sw_r_pi_dp_BB6jxb0MQHT8D-This is meant for people new to the world of startups. Most of this will not be new to people who have read a lot of what YC partners have written—the goal is to get it into one place.
Crucial Conversations Tools for Talking When Stakes Are High, Second Edition (Business Books): Kerry Patterson Corporate Consultant, Joseph Grenny Corporate Consultant, Ron McMillan Corporate Consultant, Al Switzler Corporate Consultant: Ama
Guy Kawasaki has an awesome resume and is a skilled writer. This book is about how to start a successful business (in IT). I absolutely love the language in this business book; no jargon, no marketing bs, just very clear and to the point.