Am starting the 17 Day Diet tomorrow. In the book it calls for kefir (it is similar to drinking style yogurt great for making smoothies). Does anyone know where I can buy this? I have checked walmart where they keep yogurts but not sure where in the store it is located. And also can you get flaxseed oil at walmart or any of the grocery stores? I seen a while back that walmart had the flaxseed but haven't seen the oil.