The WalMart here has fabric and it's pretty varied. The quilting cotton section has quilt shop quality fabric mixed in with the lesser cottons and it's all $4.99 a yard. The clerk told me it was going up in price any time now. One way to tell if a fabric will last in a quilt is to check the back. If the back of the fabric is plain, no color or print at all , then it will not hold up in a quilt that is used a lot. The fabric color and design is only on the surface. I would use better quality fabric in a quilt that will be used and the lesser quality fabric in my for looks quilt.
I believe there is only one fabric mill in the US. Cranston is the only working one that I know of.