well, was trying to find some CO2 locally to fool around with with a system I'm putting together. Called several welding supplies places. Either they didn't have it, or they would only do it on an exchange basis -about $25 for 20 lbs and insisting on using their tanks, and generally not being too nice and helpful... (The kind of attitude one often encounters when dealing with "professional" places when you're an average Joe off the street, I am sorry to say... And they complain why people are going to the Internet instead of patronizing the locals... ) I had read about the fire extinguisher places and was about to try to find one if there is one at all around here when I hit upon a local "Ice" place, doing mostly dry ice and supplies for beverage distributors (soda, kegs etc). The guy on the phone was nice, helpful, cordial, chatty. Went there, sort of a typical ugly looking industrial supply outfit -the kind I like. In no time at all, I had 20lbs for $15. They even threw a gasket in for free... Maybe there is still hope! Anyway, you may want to check the "keg" places around your area to see if they are not much cheaper (and nicer) than the welding places. HTH.