Basically exactly that. You can deal with one of the smaller local carriers like GAL concrete
http://galconcrete.com/ or go directly to Lafarge or Burnco. Shop around a bit and make sure you get all the fees included as different companies have different charges for things like weekend delivery, color cleanup (if you add color), small load surcharges, base delivery fees, etc. The concrete itself is only on part of the total price, so don't let yourself get surprised by delivery fees.
You usually get somewhere from 1/2 an hour to an hour to empty the truck after it shows up before they charge extra fees for on site time. If you need more than that, tell them when you order.