However, for the beginner the basics are 100% Cotton Fabric because it is easy to work with, holds a nice crease when pressed, and is just what quilts have been made with for centuries. So if you want that down home, snuggly quilt look you'll want to be sure and use 100% Cotton.
Also, be sure that you buy quality fabric if you want your quilt to last longer than say 5 years. Yep, the saying "you get what you pay for" is true in fabric purchases also. The average price for a yard of good quality quilt fabric is around $9. If you are paying say $5 a yard and it's not on sale, then you're not getting the good stuff.
Here's how I learned. When I was a beginner I fell in love with Mary Engelbreit fabrics and I bought it where ever I could find it; My Local Quilt Store (LQS), JoAnn's, and the WalMart fabric section. I made a wonderful quilt and it's been on my bed for at least 4 years. Guess which black came from the LQS and which came from the Big Box store??The Teapots came from the LQS and the cherries from WalMart. Yep the background on the cherries used to be black!
Because you are using 100% cotton in your fabric, the rule of thumb is to use 100% cotton in your thread. Yep, it's a bit more, but it's worth it. You also need to purchase quality in this area also. A quality cotton thread takes up less space when you press and your blocks will come out closer to the "true" finished size. Also, quality cotton thread will give off less fuzzies which will keep your sewing machine running smoother and you'll not have to clean out the lint as often. My favorite cotton thread is Master Piece from Superior Threads.