Duct Tape Marketing: The World’s Most Practical Small Business Guide In Duct Tape Marketing, renowned Small Business Marketing guru John Jantsch shows you how to develop and execute a . John Jantsch is a marketing expert, author and a consultant who uses its expertise to help small and medium businesses achieve their goals.. He’s the author of several books, such as The Referral Engine and The Commitment Engine. “Duct Tape Marketing Summary” Today’s marketing . In this audiobook, you will learn the Duct Tape Marketing system and how to apply its principles to your business by following three steps: First, learn the basics necessary to get customers to know, like, and trust you more. Next, master the essential Duct Tape /5().