Powells City of Books (W. Burnside & 10th St) is both the largest independent bookstore in North America and a tourist attraction in its own right. It sells new and used books - endless shelves of them in many color coded rooms.
Almost every writer who is out promoting a book will pass through Powells to give a reading and do a book signing. Make sure to check out their event calender to see what literary genius is in town this month.