Natural Gas vs Propane BBQ?

thinking of getting a bbq... i heard theres not much differences in the cooking quality of them.... however i did found some information saying the cost of natural gas is about 1/6th of the price of propane... is this correct? also where would i get natural gas? i know my water heater at home uses natural gas i believe... do i sumhow hook it up to my house or... do they sell them in tanks lik propane? i live in markham, ontario if that makes a difference