In 1975, the year's best-selling book, E. L. Doctorow's "Ragtime," sold 232,000 copies, chain bookstores were still a new concept, and the word "marketing" was scarcely heard in publishing houses. By 2000, John Grisham's "The Brethren" exceeded the sales total of "Ragtime" by twelvefold, nearly all best-selling books were published by just five publishing conglomerates, and the business was transfixed by two hot buzzwords that had no role in publishing even five years earlier-Oprah and Amazon. What has happened?