I spend from 800 to $1000 a month on food for a family of 4. It is quite ridiculous actually. But this is due in large part to having Acme as a monopoly in the area. I recall spending less than half that when I could shop at Giant in a metro area. Oh well.
Buy in bulk, on sale, and with minimal processing. Shop in different stores and ONLY buy what is on sale.
For example you can buy a lb of spaghetti for the price of one box 7oz of macaroni and cheese.