Wal-Mart and Amazon have entered a price war over books. Wal-Mart started selling 10 new books, such as the highly anticipated "Going Rogue" from Sarah Palin, for just $10. Amazon matched the price only hours later. Wal-Mart countered by dropping the price to $9. "If there is going to be a 'Wal-Mart of the Web', it is going to be Walmart.com," Walmart.com CEO Raul Vazquez said. "Our goal is to be the biggest and most visited retail Web site."