Here are my favorite places to find fabric. If you are relatively new to sewing, or you’d like a fabric refresher here is a ‘Learn About Fabric‘ crash course 🙂
They have the most reasonable prices and a great selection of Jersey and Interlock fabrics. No french terry or brush back material though.
My GO TO fabric store. They have every type of fabric, and it is sorted by fiber which is my favorite. A great selection of PUL fabric too, for anyone cloth diapering.
Have a nice variety of jersey, interlock, french terry, brush back, and ribbing fabrics. I find them a little pricey.
I like the variety of designs and you always know the quality you are getting. If you have never used Spoonflower, I recommend getting a sample pack of their fabrics. Then you can touch and feel swatches before you order. Every design is available on all their fabrics, so you get ultimate control! Here is a link for the sample pack: https://www.spoonflower.com/fabric-sample-pack
I suggest going to your local fabric and craft store to buy wovens, as this fabric type is not hard to find thanks to the popularity of quilting. If you want to do your shopping online, I like Spoonflower (same as above).
Swimwear + Dance Fabric
I also suggest going to your local fabric and craft store to buy swimwear or dance fabric, as it is really hard to determine stretch online. If your local store doesn’t have any, here is my online recommendation:
They have a great selection and are good at clearly marking the stretch direction and content.