Where do I get one of those books for my 4th grade son? He builds guns out of just about anything, including his brother’s Duplos and his own Legos. One of the highlights of his spring break was going out in the backyard at my parents’ and shooting (real guns) with his dad, grandpa, and big sister.
http://nostarch.com/legoheavyweapons
http://www.amazon.com/LEGO-Heavy-Weapons-Replicas-Impressive/dp/1593274122