The Friends of the Louisville Free Public Library will have their annual book sale this weekend.The group’s Lauren Kallmeyer says the sale will take place at Butler High School.“The bulk of the money that we use to fund programming at the library come from this book sale, so a lot of this programming that the library does not have money available comes from the Friends of the Library.”A preview for Friends members will be held tonight from 6:00 to 9:00.The public sale is from 9:00am-5:00pm tomorrow and 1:00pm-5:00pm Sunday.