Use this Excel-based bias calculator to calculate fabric needs for creating your bias strip. Enter the dimensions of your quilt and the width of the bias strip you’d like to use, and it will tell you how big the square of fabric needs to be to cut the strip. Or enter the dimensions of your square of fabric that you have and the width of the bias strip, and it will tell you how long a strip you can make.
I use Jinny Beyer fabrics for most of my projects.
If you don’t already have the Keepsake Quilting catalog delivered to your mailbox, you should. Their website is an excellent selection of fabric, books, notions, kits, and more. Very easy to deal with.