Barnesandnoble.com on Thursday unveiled a multimillion-dollar advertising campaign featuring such well-known authors as John Gray ("Men Are From Mars, Women Are From Venus") and Scott Turow ("Personal Injuries"). In the commercials, writers personally deliver their new books to consumers' homes. In Gray's case, the author counsels spouses who can't agree on whether to read his book. The online book and CD company did not disclose financial details about the campaign, designed by TBWA/Chiat/Day. The ad campaign features the tag line, "We Bring Writers Home."