Our JoAnns had more after the move - TWO bolts of each of the same eight or so fabrics. You could read the newspaper behind some of them.
I buy backing online from Christian Lane Quilters, Eleanor Burns or Hancocks of Paducah on sale. White or natural muslin can be bought in large yardages from Hancocks of Paducah or Marshall Dry Goods (online).
My most recent visit to Joanns revealed the prices were much higher, and the sales not as good. A 40% coupon on one item doesn't help much when you are buying 1/2 yard pieces. AND the 15% coupon off your entire craft purchase excluded fabric.