I shopped at Rainbow Grocery several times while trying to improve my eating habits. While a small store, they still have an excellent selection of organic fruits and vegetables, bulk foods, and a pretty impressive choice of other natural foods...including frozen foods, pasta, soups, and snacks.
Prices were quite reasonable, considering that you are buying organic and natural foods.
They also have a smoothie shop right in the middle. Feel free to order shots of wheatgrass as well! (Although I'd recommend just adding wheatgrass to your smoothie!)