If you have any tractor supply type shops around you can also find giant bags of aspen bedding for cheap. Even at my local small pet shop I can get a huge bag for about $15 or less (They're a bit pricier than some places but they've been around since I was a kid and I've always appreciated how well they take care of their critters. They even breed their own parakeets, and I've never seen another place with such big healthy 'keets)