Google is taking aim at online retailer Amazon.com, which offers similar technology on its e-commerce site and recently invaded Google's turf by launching a rival search engine, A9.

Google reaches a much wider audience than Amazon. Google had 63 million visitors in August compared with Amazon's 31.1 million, according to measurement firm Nielsen/NetRatings.

"Our mission is to organize the world's information, and bringing books into the index is a natural part of our evolution," says Susan Wojcicki, Google's director of product management.

Google is offering the Print.google.com (http://print.google.com) service to publishers for free. They can send their books to Google's offices in California, where staffers will scan specific pages and place them into the index.

Google profits by adding its text-based advertising below its book pages. For example, a search for books on rock climbing features ads for rock-climbing gear.

"It's interesting to see the focus move from Google vs. Yahoo, to Google vs. Amazon now," says Chris Winfield, president of New York search marketing firm 10e20. "I'm delighted to see my ads show up on the book pages, but as Google's first post-IPO announcement, I'd have rather seen it be the browser."

Winfield was referring to rampant Internet-based rumors that Google will offer an Internet browser to rival Microsoft's Internet Explorer. It reportedly would work in tandem with Google's search, e-mail and photo-management tools.

Mark Mahaney, an analyst with securities firm American Technology Research, says the book search "speaks volumes, excuse the pun, about how serious Google is about trying to categorize and search information on and off the Web."

Google has a ways to go to catch up to Amazon. Google has just a handful of books online so far; Amazon has more than 100,000.