Harry Potter the new marketing bible

If you need a good reason to read Harry Potter then Stephen Brown a professor of marketing might have some reasons:

"The basic argument is that Rowling, far from being hijacked by the marketing sorcerers who have exploited her innocence, is actually something of a marketing professor herself, even if she has never had a day's academic education in the subject. She has created Harry Potter using branding techniques and the books themselves are full of brilliantly invented brands, corporate strategies, advertising campaigns and every element of the marketing mix. In effect, they make a textbook case for marketing." more

Now if someone could tell me which Harry Potter book I should read first.