Just over the Brooklyn Bridge there's a delightfully large bookstore in DUMBO called powerHouse--its the coolest spot in Brooklyn to see art and books in a big open space. powerHousegets loads of local and national authors into the store, so check the announcements to see what's going on. They don't mind browsing so grab a stool and peruse some books before picking out your treasures.
37 Main Street
Brooklyn, NY 11201