The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.
www.aquariumplants.com has an empty 5lb aluminum canister shipped (to me in MI) for about $66. That's not a bad deal at all and you most likely won't find better. When I was looking at cansiters several months ago I think the cheapest I found was in the low $70's including the link mentioned.
Do the math. I found that buying a 'cheaper' tank online, having it shipped, and then having it filled was the same price as just buying a filled one from my local Robert's Oxygen.
YMMV - you just might want to check it all out. Refills alone cost me $21