Just to go ask the question...I'm not sure what you mean by "maps of DnD". There is the World of Greyhawk which is considered the official/default game world that is used. The truth to this statement, though, can be argued. It is the default game world for the gods listed in the Player's Handbook. I'm not sure where you would find those maps, but I believe if you did a google search on images, you could find something for "greyhawk".