I actually got this info from a independent documentary called "Iraq for Sale". I'd have to watch it again to get specifics because i saw it a couple months ago, but the jist is that everything you can think of in this war is being bought from companies by the US government. Military training is being done by security companies with Ex-Marines doing the training. Interogations of prisoners are being done by civilians. Equipment are being made by corporations, which means they are sacrificing effeciency and durability for cost. There's even companies that do laundry and serve food. The mess hall lines take hours and the laundry detergent give the soldiers rashes. And when the soldiers try to do their own laundry, their officers give them a swift kick in the nuts cuz this company get like 99 cents a load and get pissed when they lose one.
I suggest you look it up and watch it for yourself. You think the cost in Iraq is just the gas we're using to get the soldiers around? Think again.