Where can I buy fleece fabric for cheap?

I wanted to use it for my rats cage and I also need something to make their new hammocks out of. I checked wal-mart, and they only have blankets for $14. There's a k-mart and a michaels arts&crafts store near me, but I think michaels would be kind of expensive. Can anybody name some stores I can buy the stuff at? I live in southern delaware if that helps any.