The Wooster Friends of the Library will be holding its annual Spring Used Book Sale tomorrow and Saturday.  Hours tomorrow will be 9am-4:30pm and then 9am-2pm on Saturday.  The sale will take place in the basement of the library’s operations center, which is located at the corner of NorthMarket and Larwill streets.  In addition to thousands of books, the two-day sale will also feature DVDs, CDs and books on CD.