[bendyfoot]

First off, the raw thing is pretty easy actually. There's very little "preparation", just shopping, freezing, thawing, and handing over the food. If you look in the food section of this forum you find there's a section just for raw feeding, you can get an idea of how to start. But to give you an idea today Jaida will eat a whole chicken leg including bone, a chunk of pork shoulder, and a peice of beef liver or kidney. The type of protein really doesn't matter unless there's an allergy involved, and it's basically a ratio of 75-80% meat, 15% bone and 10% organ/offal. Meats we like are pork, chicken, beef, sometimes lamb or venison if I can get it. Butchers are great sources of cheap meat and organs if you buy large quantities.
You CAN buy packaged, prepared raw diets, which I do for my cats (although I supplement with whole chicken backs so they get the dental benefits of the bones, not just the nutritional benefits of the ground bone in the prepared foods), but the amount of food you have to feed a large breed would be extremely costly. Doing it yourself if much cheaper.

Second, if you decide to try a different type of prepared dog food instead, please please have a look at the food forum for ideas on healthy foods for your dog. Iams, Pedigree and pretty much any food you can buy in a grocery store is pretty much garbage...it's full of corn and other nutrient-poor fillers. Consider a grain-free food like Orijen instead. It's a little more pricey, but honestly it's cheaper in the long run because you'll have a healthier pet. If you're in Ottawa, try Critter Jungle on Carling at Kirkwood or Global Foods on Bank in the Glebe...they've got great selections and knowledgable staff.