I would scope out some local farmers markets. The produce will most certainly be fresh-er, the prices cheaper (for more food), and you will be supporting your local farmers.
I've found that for the same price ($5), I can get twice as much fruit of a selected variety at the farmers market than I can at the brick and mortars.
The other thing is, if you have the space, inclination, capacity, or all of the aforementioned, you can grow your own food. That's actually the new trend. Those upside-down planter things? Only $10 at BB&B (with a coupon, of course) and you can grow tomatoes and other veggies indoors - free food right there.
The other thing is if you're more into meats and whatnot, DO NOT be afraid to go to your local brick and mortar stores and scan the clearance meat section. These meats are 1-3 days away from "expiring", so the store is trying to clear them out. In all honesty, if you buy what you want and then freeze it, you'll be fine. Meat at the store is NOT refrigerated, and hence why the high turnover. I've been able to get rump roasts, chickens and ribs at 70% off. But make sure you either cook it immediately or otherwise freeze it.
Another thing is, if you can get several friends who like meat together, you all can get together and purchase a cow. That's right, a cow. Your money will be pooled together to purchase, feed, house, store, and eventually butcher the cow and you all get to pick what parts you want. This can work out splendidly and the cost isn't that much, around $50-100, depending on how many people go in. However, the more people who go in, the less your share, so consider that. The upside is that you get A LOT of mean. My friend went in on this with several other people and he got enough meat to last 2 months. We had to use my freezer to store the extras (which, of course, was paid for by my being able to use some meat