Get as much as possible during the summer and preserve it. Our growing season is pretty short so right now my freezers are crammed full of produce to last us the winter. I do buy some canned fruit, but otherwise we stick to fresh apples and bananas in the winter for fruit and eat all the veggies I've frozen.
Look for u-pick farms, check craigslist and freecycle (people always have too much and try to give it away or sell it cheap). I even got a huge bag full of fresh corn on the cob yesterday at the bus stop because the chopper broke down and the farmer didn't want it to go to waste. Ask around, check out your farmer's market and see if you can swap some labor for produce.
I don't know, I may be the wrong person to answer that. I live in a very agricultural area and get lots of free produce by swapping or just hearing about how someone's got something extra and going and getting it. I have lots of friends who garden so we swap things all the time.