I will go through our "stuff" collected during our stay earlier in August and see if I can find a map that was given to us at the Concierge desk at the Fort. This map was produced by one of the rental car companies and included more detail on streets outside of the "World". I don't recall there being any other businesses listed on it, but we used it along with the Unofficial Guide to venture into foreign territory!
In all my reading, I think the Unofficial Guide probably has the most detail on the businesses around WDW and their maps are pretty good. I have not done a lot of digging around the web to see what is available, just don't have that much free time on my hands anymore, but I would figure someone has this published.
One thing I found interesting, all of the stores on Disney property can only sell Coca-Cola products, including the Hess stations. I had tried to pick up some Mountain Dew for my son and his friend, and the guy behind the counter said that Disney makes them enter into marketing agreements in order to lease space on the property. I had asked because Hess carries Mountain Dew in other locations.