I have been buying sheets at our local thrift store to use for backing. I'm careful to get all cotton and new or near new, high thread count. Got lucky last month and got a luxery king size white sheet for $2. It's the only way I could afford to have backings on my quilts!!!!!!! I also keep a lookout for batting (I have found unopened bags for 50 cents). I'm hoping to find a nice cotton blanket to use as batting for a quilt I'm making for my grandson.