Guru Stephen Covey has proved a highly effective author for Simon &Schuster, with 10 million copies in print of his first book, The 7 Habits of Highly Effective People, alone. Now he and his staff will produce five more books and audios in a deal that sources say is in the eight figures. First up: The Power Principle: Influence with Honor in hardcover in May and First Things First Everyday: Because Where You're Headed Is More Important Than How Fast You're Going in Fireside trade paper in June.