The Walmart near where I live (Buena Park, CA) has a really good selection of Atkins products and they seem to be adding more on a regular basis. Everything is also about half the price of the grocery stores, but I'm not sure about GNC since they are way to overpriced to begin with (just my opinion). This is a newer store, so that might make a difference since I don't know if all the stores have a "low carb" section.