The first Saturday of each month, the El Dorado County Main Library at 345 Fair Lane, Placerville has a used book sale.  For $5 per grocery bag that you stuff full of books (or $4 if you bring your own bag), you can stuff it with things like books, games, tapes and so on.   Drive into the parking lot in back of the library. It runs 8am to 2pm.  Don't forget, you can donate books to the library too!