Bookstore sales rose 1.6% in March, to $1.01 billion, according to preliminary estimates released this morning from the U.S. Census Bureau. For the first quarter of 2010, bookstore sales were up 1.2%, to $4.32 billion. Sales for 2009 have been restated as were sales for January and February. For the entire retail segment, March sales rose 10.8% and for the quarter were up 6.2%.