What to read after Think and Grow Rich?

IN EVERY chapter of this book, mention has been made of the moneymaking secret which has made fortunes for more than five hundred exceedingly wealthy men whom I have carefully analyzed over a long period of years. The secret was brought to my attention by Andrew Carnegie, more than a quarter of a century ago. The canny, lovable old Scotsman carelessly tossed it into my mind, when I was but a boy. Then he sat back in his chair, with a merry twinkle in his eyes, and watched carefully to see if I had brains enough to understand the full significance of what he had said to me. When he saw that I had grasped the idea, he asked if I would be willing to spend twenty years or more, preparing myself to take it to the world, to men and women who, without the secret, might go through life as failures. I said I would, and with Mr. Carnegie's cooperation, I have kept my promise. - From Author's Preface