Not sure if this is the right terminology to use.

(yes, I know how to go to the store and buy a quart of oil)

Okay, oil is like $35/barrel (let's just say it is)

We all know it's going to go up at some point in the "near" future.

How would one go about buying "shares" of oil (I know it's traded on the
commidity market, so perhaps that's where you buy it)?

Too bad our government doesn't take some of that $700 billion and buy
some oil and then when the price (inevitably) goes up, they could sell
it at a discount to the US, make some money back and "help" the economy
by selling oil at a cheaper price? (although I'm sure there's some law
somewhere that prohibits that, but for some strange reason lets them
waste the rest of our taxpayer money).