Kent Feed/Blue Seal can be purchased at Do It Yourself Centers if you have any out there. I think the Blue Seal is a very good feed. Making your own can be complicated to make sure the chickens get all the necessary nutrients.
Not sure why people don't want soy in the chicken feed. It's healthy for chickens and people. It is hard to know which feeds are good and which aren't. I know when I buy generic food at the store, it isn't as good (taste wise) as the name brands. I would assume it would be the same for chicken...