My new eBook, Marketing with A3 utilizes A3 thinking and enables you to apply a systematic method of problem solving to your marketing and sales. If you want to learn more about the A3 thinking process, this is my recommended list. There is little duplication of material between these resources and I think you will benefit from each and everyone of them. Tracey’s Business901 podcast on the Lean Problem Solving was excellent and would recommend you would start there. 
In Understanding A3 Thinking, the authors first show that the A3 report is an effective tool when it is implemented in conjunction with a PDCA-based management philosophy. Toyota views A3 Reports as just one piece in their PDCA management approach. Second, the authors show that the process leading to the development and management of A3 reports is at least as important as the reports themselves, because of the deep learning and professional development that occurs in the process. And finally, the authors provide a number of examples as well as some very practical advice on how to write and review A3 reports.
Managing to Learn by Toyota veteran John Shook, reveals the thinking underlying the vital A3 management process at the heart of lean management and lean leadership. Constructed as a dialogue between a manager and his boss, the book explains how A3 thinking helps managers and executives identify, frame, and then act on problems and challenges. Shook calls this approach, which is captured in the simple structure of an A3 report, the key to Toyota’s entire system of developing talent and continually deepening its knowledge and capabilities. The A3 Report is a Toyota-pioneered practice of getting the problem, the analysis, the corrective actions, and the action plan down on a single sheet of large (A3) paper, often with the use of graphics.
The One-Page Project Manager set a new standard as an understandable and easy-to-apply organizational tool, allowing managers to summarize complex projects on a single information-rich page. This book, third in the OPPM series, describes how to combine the OPPM with the Toyota A3 report to create an enhanced, integrated management tool.
The A3 Workbook: Unlock Your Problem-Solving Mind is designed to teach A3 Problem Solving to workers at every level of an organization. This workbook provides a practical tool for solving specific problems or for making a specific proposal, while also encouraging the development of a corporate culture that empowers all employees to support continuous improvement. The workbook follows the progression of a basic A3 Problem Solving format, offering instructions every step of the way.
Podcast on Lean Problem Solving: Is Problem Solving the Core of Lean Implementation?
Related Topics:
Starting with Lean A3 Thinking in Marketing
Introduction to Marketing with A3
The 7 step Lean Process of Marketing to Toyota
Best Marketing Advice Ever, yes Ever!
Lean Marketing is a Problem Centric Discipline
Online collaboration is leading the way for Lean Marketing