Where do you guys and gals get your CO2 filled? There's a couple paintball places around here and I've gotten my paintball tanks filled there, but only up to 20oz...I'll have a 10lb tank. Will they still fill it?
I usually got to a welding supply store. I also have a sporting goods center near my work that will fill paintball tanks and regular cylinders. Fire extinguisher places may also be able to fill for you. Some places will only do a swap instead of filling your cylinder. I only go to places that will fill my cylinder.
Today I called some local fire extinguisher places until I found one that sells and refills tanks. It cost me $75 for a full five pounder (or would have been $85 for a ten pounder). Refills are $15 or $20. That's WAY cheaper than the local fish store which wants $185 for the tank and $35 to swap it for a full one each time it's empty. So I'd suggest calling extinguisher stores...
Airgas exchanges a 15# for $28.00. They take the cheap aluminum ones you buy on eBay in trade, and let you trade up for just the cost of the refill, so if you buy a 5 or 10#, you can end up with a 15#. Refills cost almost the same for the different sizes. Sports Authority refills my 24oz paintball tanks for $3.50, every tenth fill is free.