Health food stores and food co-ops often have it. Or they can order it from their distributors. In my area Fred Meyer (Kroger) carry it as well. They use one of the same distributers (UNFI) that health food stores use so have a lot of organic choices.

I think my daughter got it at a place like Whole Foods

Look for it in the specialty food sections and not the soda aisle. My Giant in PA carries it in a small section with gluten free and organic foods.