Whoaaa, these things are expensive. Is there something I don't know? I see that a lot of people on here are using pressurized CO2 in their tanks, but are you all shelling out the $300+ to get all the equipment? Is it cheaper just to buy all these parts on your own, and use a paint-ball canister or something?
You can get a Milwaukee or Azoo regulator complete with solenoid and needle valve along with a 5lb tank for under $150. Then you just need some tubing and a method to dissolve the CO2 such as a glass diffuser, inline diffsuer, reactor or powerhead with a needle wheel typ mod. You can find decent glass diffusers for under $40, a DIY reactor would probably run around $30 for parts as would a powerhead. If you're using a canister filter you can always give a shot at using it as a reactor also.
Some people have money and some have time.
Patience is the important part. Luck sure helps too.
One consideration is where you live. Is Poulsbo anywhere near a Craig's list city? If so, use the search feature on the for sale section and search daily for CO2 until you find a tank that will fit in the space you have. Looks isn't as important to me as the price, but I lucked into an aluminum tank that ended up costing a ridiculously low amount.
As for the rest of it, careful shopping which is easier after you know what you are doing, can provide bargains.