If you merely want to save money, switch to a layer mash available at most feed mills. It is often MUCH cheaper. For treats....most veg/fruit table scraps, rice, couscous, etc. I buy bags of beans at bulk stores, and sprout for winter treats.
There's a great thread about homemade flock blocks on here. Mine has:
1.5 cups crushed corn
1.5 cups bird seed
1/2 cup flax seed
some random cooked quinoa, and barley that I had leftover from previous meals
1/2 cup raisins
about 1/4 cup soy butter (you could use peanut butter....I had this lying around, lol)
4 LARGE eggs
Some oatmeal for binder.
I then baked it at around 325 or so for an hour. I can't remember if that's EXACTLY what it had in it, but that's it for the most part. I baked mine in mini bundt pans (like you'd use for lava cakes). They came out great. You could also do them in muffin tins, or a cake or loaf pan.