airgas is probably more expensive than, say, harbor freight. many online brew shops sell them for less than that price too. my LHBS fills a 5lb tank for $14.
I used to have a place close by that would fill cylinders at a good price. They moved 30 miles away.
Now the best deal is a cylinder swap at $20.00 for a 20 lb tank. You might be able to pick up a used tank from craigslist and get it hydrotested for less than the $140.00.
Wow those are some great prices. Thanks for that link. Plus, they clearly state their cylinders have been tested. Who here has saved a few bucks and went with the reconditioned steel cylinders?