A few useful links:
- The Appalachian trail Conservancy (ATC). The keepers of the trail.
- A Google Map of the AT.
- The National Park System strip map of the AT. Probably one of the best maps of the Trail. It is in .pdf format and you can zoom in/out for additional details.
- A google map of shelter locations.
- Whiteblaze.net is an excellent source of AT information.