Here's some interesting facts, figures we put together on propane, A.K.A. LPG...

store (DOT) intellaliftparts.com (DOT) Propane.html

thought I'd pass along.
I'm gonna guess that the majority of internal combustion trucks in North America run on LPG. Not diesel, not gasoline, but LPG.

One thing that has surprised me as a parts supplier, is how there are regions of the country where we sell new LPG tanks, and other regions we sell zero. In our state of Michigan, most of the LP gas suppliers will provide a no-charge outdoor storage rack, and tanks at no charge exchange basis, provided you buy the LP gas from the gas supplier.

What is it like in your market? Do the LP suppliers give away free tanks? Or do you need to pay for them? Or do you only need to pay for them if you have a bulk tank (but then really, how often would you replace a tank, seems like they last a long time)