NEW YORK - Giving away electronic books online is the way to sell more books overall. That was the consensus at the Google Unbound conference of top book publishers and invited authors Jan. 18 at the New York Public Library. Google recently raised eyebrows with its Google Books project, a plan to scan all public domain books for an online public archive. The Unbound conference focused on the marketing potential of offering free books online and the benefits of the online channel to target the segmented industry that makes up book publishing. Giving away free electronic versions of a book is the smart way to distribute content, said Chris Andersen, editor in chief at Wired Magazine and author of The Long Tail. The Web site for Wired doesn't cannibalize the magazine, it just distributes the message to a potentially infinite amount of people at no cost. It doesn't take away from sales because the whole experience of reading long articles with glossy