After a lot of time and effort HikeArizona.com now hosts the most comprehensive, detailed, and easy to use interactive
map of Grand Canyon backcountry
use areas. The NPS doesn't have an online map available -- they tell you to buy a paper map! Some other sources have rudimentary drawings. Nothing compares to this though! You can find a link to it at the bottom of all description pages for Grand Canyon hikes here on HAZ.
You can also get there directly anytime by using this link.
Click here for the Grand Canyon Use Area Map
Enjoy your new, easy Grand Canyon backcountry planning tool!
Special thanks to Joe for his programming wizardry, and of course to Hikebot who is still nursing it's injuries with a Costco-sized case of WD-40!