I will never, ever pay $12-15 / yard for fabric. Never! Right now I have so much fabric that it will be a miracle if I am able to use it all before I die. And that's with sharing with my future DIL! With the exception of special fabric that I bought online for a quilt for my son at $7.99/yd, I never pay more than $3.99/yard - and cheaper than that is better.
I shop at Joann especially the Red Dot section when it's 50% off. I've gotten lots of quality Debbie Mumm, batiks and other designers and the quality has been top notch - which I can't say about the pricier stuff I've purchased online. I also shop at Walmart but I will admit you have to check the designs to be sure there isn't a logo mixed in with the designs. My very best bargains have been at estate sales of quilters. At one I filled my car until there wasn't an inch left and paid $120. That one was at a destashing sale of a fabric and project designer who was quite alive. At another I got tons of batiks and other goodies enough to fill my trunk and part of the back seat for $50. There is a wholesale fabric place near us, but the prices aren't that low and the fabric is very thin so I stay away except for some laces that I use for my veil making business.