Home Depot is having a sale on the Mr. Heater knock-off. It doesn't list a 20lb adapter as an option though I imagine it would be very straight forward.
Can the Coleman 2 burner be hooked up to the larger LP cylinders? The multi fuel stove I found is here:
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200234424_200234424Thanks,
M