The Food Stamp Nutrition Connection has a recipe database which tells you the AVERAGE cost per serving of a whole lot of recipes. You can search for ingredients or browse by category. The costs are based on a national average, adjusted for inflation (but perhaps a bit behind right now). It doesn’t show you what it costs you in your area so your actual costs may be more or less but it’s a nice dataset to have for a starting point.

http://recipefinder.nal.usda.gov/