Get in touch with dog show people in your area. I think there are groups on Facebook, etc. You should be able to buy raw food in bulk like we do. We will split a box of chicken backs with our daughter. It works out to $.29/lb. We also get duck necks and various other parts that the slaughter houses virtually give away. This means you need to have a freezer. We have a 15 cubic foot upright.
We try to sign up all our puppy clients on the B.A.R.F. World flash frozen raw food. It is a lot easier to handle then the above mentioned ideas. They ship you this directly to your house in a styrafoam freezer box.
http://barfworld.com/what_is_barf.php
You can probably split boxes of parts with someone else that lives within 10 miles of you. We also supplement with canned squash or pumpkin. When it goes on sale, I will buy multiple cases. It always goes on sale prior to Thanksgiving. There are also coupons you can get from Libbys on EBAY to cut the cost down. You can also add green beans(canned, frozen, fresh). Carrots are also something to give them in their crate time to keep them busy.
Most of the dry dog food is just filler. It is indigestible for your dog. Therefore, it goes right through them. This means that you eventually need to pick it up. With raw, that is reduced by at least 50%. Also, dogs that can not lose weight, shed it on the raw diet. Dogs do not need carbs.
Thanks so much. I would have replied sooner but just now caught this.