One of my favorites is "Heirloom Beans" by Steve Sando
http://www.eatyourbooks....-beans-great-recipes-for
It has recipes for heirloom varieties that allows their unique flavors and colors to shine. One of the only places you will find recipes for tepary beans, good mother Stallard beans, Swedish brown beans, and dry scarlet runner beans (and many more heirlooms) all in the same place.
A related book is "The Rancho Gordo Heirloom Bean Grower's Guide", also by Steve Sando.
http://www.eatyourbooks....ordo-heirloom-bean
It only has a few recipes but it includes information on 50 heirloom varieties, with suggestions on how to use them in your cooking. Most of them (but not all) are tricky fo find in the supermarket (unless you buy the Rancho Gordo brand or buy on the internet), but since I grow my own heirloom beans this one is quite useful for me. I'm not sure what your project entails, but this might be a good resource to show some of the great diversity in the bean family.
They are both indexed and have lovely color photographs.
Another book I use is "366 Delicious Ways to Cook Rice, Beans and Grains" by Andrea Chesman (also indexed). http://www.eatyourbooks....cious-ways-to-cook
The recipes in this one are pretty standard, calling for everyday beans anyone can find in the supermarket, but it's nice to have so many bean recipe options gathered in one place. My favorite recipe from this one is the "White bean chili verde" - I had some incredibly productive tomatillos in the garden last year, and this is a very tasty way to work through those many pints in the freezer. :)