This applies to ANY item, ANY length, including Dollar Downloads! For every purchase, you're automatically entered into the drawing, so it's mega easy. And it applies to all the other awesome books Echelon sells, too. These make awesome Secret Santa and Hanukkah Armadillo* gifts. You can take care of, like, half your shopping list all at once.
*reference to the TV show "Friends" and no disrespect intended, only laughter.