Some Walmarts sell Lorann flavorings (but avoid any that are really oils - i.e citrus, almond, and some others, because they are a lot harder to use in e-liquid)
See the Guide to DIY Flavoing in the sticky threads in the DIY section of this forum - it marks which flavors are not water soluble.
DIY e-liquid
And you can also get Loranns, Flavourart and perfumer's Apprentice flavorings at OneStopDIYShop.com as well as everything else you might need