I second everything that mistymama said. Raw has nothing to do with the size of the dog, many people use it for toy breed dogs and cats. My dogs are 35 and 75 lbs so there are certainly differences in what size items I feed them, but you get used to it quickly. At the beginning I got an inexpensive food scale and after a couple of months I got comfortable with the whole process and started eyeballing it. If the dogs start to look a little heavier I feed a bit less and if they're a little thinner I feed a bit more. I've found that it's much easier to both put on and take off weight on raw. You certainly don't need a scale though - if you shop at a grocery store the package will have a weight marked on it and you can just divide by how many items are in it to get a rough idea.
And as mistymama said you will want to choose one type of meat to start with (many people choose chicken because it's easy to get, inexpensive, and the bones are very soft). Give that a few days to a week and then introduce a second meat. It's important to give a variety of proteins and animal body parts since they bring different nutrients to the table - for example dark chicken meat is different than white chicken meat, red meats have more taurine, etc. I would aim to have at least 3-4 different proteins in your rotation eventually.
Once your dog is used to the different meats you are feeding you'll want to add in organ meat (liver and kidney are the main ones, but you may find others which are good also). Keep in mind that heart, although an organ in terms of body function, is considered a muscle meat for doggie feeding purposes. The ratio I aim for is about 75-80% meat, 10-15% bone, and 5-10% organ (with about half of that being liver). No need for veggies or carbs, though personally I'm not entirely anti-carb and do make my dogs simple homemade cookies as ocassional treats.
Here are a few good websites:
http://www.rawfed.com/http://rawlearning.com/http://rawfeddogs.net/ - Click on the Recipes section, then the item, then the item's photo. They have photos of all kinds of dogs eating their raw food, cats also!
Oh, and we feed in their crates (that's all they are used for anymore, but it helps keep the positive association in case we ever need them). We've also fed on easily washed floor (tile, laminate, linoleum) when visiting family. Let us know if you have questions - we'd love to help!