The receipts received for services offered by a retail bookseller’s through a preferred reader program were subject to transaction privilege (sales) tax. The services aimed at encouraging customers to purchase the bookseller’s merchandise were considered a part of the sale of the merchandise. (Walden Books Co., d/b/a Waldenbooks, Arizona Court of Appeals, Div. 1, No. 1 CA-TX 99-0022, November 2, 2000)