The above graphic was created using a Windows bitmap created by Adam Jones and posted to a classic video game newsgroup. (I forget which one.) I enlarged this as a bitmap and I am/was (depending on my whim) using this as my Windows background. If you'd like to use this bitmap to create your own scenes, here it is:
Available in the original .BMP format (use "load to disk" or equivalent) or as a GIF.
Cudabert has created a map using this image. Although it doesn't look quite finished, it's very good. The map and other stuff is available from his FTP site.