If you have access to a Farmer's Market, they usually have organic foods at much cheaper (and fresher) than you can get at the store. And if you get to know the farmers they can often give you names of people who don't sell at the markets, but have products you might be interested in like raw milk or eggs. Sometimes they'll even let you come work at their farm/garden in exchange for mentoring or free products.
We bought a quarter of a grass-fed cow this year and the price came to a little under $4 a pound. Next time we'll get a half though! We found them by talking with friends who knew someone and that led to our purchase. We were also able to buy organic local wheat at $6 per 25 pounds by talking with someone. I've found that if I just start talking about stuff usually someone can direct me to someone who can tell me about someone.....
You can use the Eatwild.com website to find local producers or contact someone in your local chapter of the Weston Price Foundation.
Keeping things really simple helps too. I could create fantastically gourmet organic meals, or I can create simple, nourishing bean dishes, soups, salads, etc. I'm learning to work with what I can find locally or cheaply online and not envy or moan about those things I can't afford.
Yes for gardens! If you have room try berry bushes and fruit trees. And if you can manage it, raise your own chickens and cows (for milk and meat).
We have a "necessary only" rule most of the time. I use our grocery money for what is necessary, not fun or nice. Organic fruit snacks are fun and nice, but aren't necessary to our nutritionally development. Same with chips and crackers and other such stuff. We do buy them on occasion, but mostly I try to focus on filling our bellies with healthy, satisfying foods.
I'm not the greatest at this though so I'm hoping there are lots of other ideas!