If you don't grow your own fruit and vegetables, buy your produce at farmers' markets and at stores working to provide organic local produce to their customers. 
Tell your grocery store how important it is to youfarmersmarket-8-07.jpg and how much you appreciate their effort. 

Buy in season. Plan meals that feature what's really tasty right now. You'll have the freshest, most flavorful, well-rounded and healthy food possible, and at a much lower cost than out of season tasteless imports.

At the farmers' markets, notice where the farmers are coming from and choose to buy from the closest farms that haven’t traveled hundreds of miles. See how local you can shop! Read Barbara Kingsolver’s wonderful book, Animal, Vegetable, Miracle; A Year of Food Life to really understand the seasons of the foods we eat. 
Got picky eaters? Children who get to eat fresh local vegetables in season are much more enthusiastic and healthy eaters, and those who get to help grow their own are the most enthusiastic of all. 
People who shop at farmers' markets have many more healthy social exchanges, leading to overall well being, and then in some cases there is live music. Ah! This is the life. 
There are lots of farmers markets in Marin County. Some are year round, some are seasonal. Check out the schedule and locations of farmers' markets near you. 

Sustainably harvested seafood guide.

Why is eating organic so important? Read this article.