Foust Textiles during there two open weekends each year (February and August) in Kings Mountain NC - You can buy whole bolts for $3-5 per yard. They do have some prefolds they sell by the pound and I figured out after I got home in February that they ended up less than $2 per yard. I am hitting that section first in August!
Marshall Dry Goods
Hancocks of Paducah
Honestly I live 30-45 minutes from MaryJos in Gastonia and it is just not what it used to be. A much lower level of quilt fabric inventory and higher prices since MaryJo turned the business over to her kids. I have a friend who was friends with MJ and MJ's goal was to not charge more than 30% over wholesale to keep quilting affordable. Now they charge at least 100% over wholesale. They clearanced out a lot of the old fabric and no longer have scrap bins. If I were very close I would stop if I had nothing else to do, but wouldn't make a trip out of it!