Is this the pattern you are talking about?
http://quiltbug.com/free/table-topper.htm
I think the reason she is calling for fat quarters is that a lot of people collect those and are looking for ways to use them. You can use any piece of fabric, just read what the cutting requirements are for each color and make sure you have enough material to cut the pieces out of every color. I don't buy fat quarters, so would be cutting this out of yardage.