Learning as I sew means I do not want to pay a lot for fabric in case I mess up. I'm not ready yet for Burnley & Trowbridge.
So far, I've been pretty fortunate, except for the aforementioned first crack at the puffy peasant shirt. If you need to start with cheap fabric to hedge your bets, the place to go -- at least in Phoenix or Tucson -- is SAS Fabrics.
I've found SAS to be like Goodwill for fabric. Look hard enough, long enough, and you'll find treasure. The location on Speedway in Tucson is where I first starting picking up material for the puffy breeches, followed by the long red coat.
Be forewarned: digging around in some of the piles of fabric can be tedious, but it's worth it. However, I soon discovered their more ordinate Phoenix superstore:
This one is not only bigger, it's more neatly organized. That's how I discovered the satin jacquard for my latest coat project. If only it were closer to Tucson.
My second pick is Hancock Fabrics. Madame Sherri was visiting your humble servant in Tucson when she noticed it as we were driving somewhere else. "You have a Hancock Fabrics?"
"Yes," I said, puzzled. At the time I didn't know two things: 1) Phoenix doesn't have them anymore, and 2) They have a crazy amount of sales. I don't think I've ever seen them at a time when something wasn't on sale. I'm now on their equivalent of their "frequent fabric" card.
A lot of you will swear by Jo-Ann. Nothing wrong with them, and they do offer loads of classes. Fabric for your humble servant's first Puritan outfit came from them. Hobby Lobby also stocks some good finds. A lot of people have also pointed me to Fabrics.com, but I prefer to look at something up close with my own eyes before buying it.
And remember... patience and persistance pays if you're looking for just the right print.