The Online Video Game Atlas has a lot of fine maps based on screengrabs directly from the games. Some time ago I downloaded Zebes from the NES Metroid. Why mention this now? because my apple g5 comes to a screeching hault every time it loads up on my wallpaper (which rotates a new image from my picture folder every 5 minutes). A lot of these maps make excellent desktop images for your computer, and serve as pixel-accurate references for anyone playing these games. Reminds me of my old Nintendo Power player's guides...