I have bought fabrics online at Joanns, very pleased with it. I have bought even more at local stores, both were good deals.
I recently bought backing fabrics from another popular store, was sent twice as much as I thought I ordered. I won't buy from them again. One piece even had a perfect 4-5" square cut out of it. Luckily I was able to cut a backing and by passed the cut out square. Just won't buy again. Good thing I have lots of fabrics and don't really need anymore.