I want to take a page to share some of the resources that I have come across. I have spent a year researching and reading to prepare me for hiking the Appalachian Trial and thought it would be helpful to put all that info on one page for anyone considering hiking the trail in the future.

Books I Have Read:
A Walk in the Woods by Bill Bryson
A humorous story of his attempt to thru hike. You will not gain any knowledge or tips from reading this, but it will make you laugh.

Just Passin Thru by Winton Porter
A great book about some of the characters you will meet on the trail

AWOL on the Appalachian Trail by David Miller
A great account of his thru hike and probably one of the most popular thru hike accounts out there

On The Beaten Path by Robert Rubin
Taken from journal accounts of his physical and spiritual pilgrimage

Long-Distance Hiking by Robert Mueser
Reads more like a text book but loaded with great information to help prepare you for the long haul

Appalachian Trials by Zach Davis
The newest book to come out about the trail could also be the one that will keep you on the trail. Zach looks at the mental and emotional challenges that defeat more hikers than the physical. Looking at it openly, honestly, and with humor, he gives tips to not only get your mind ready for a six month journey, but also how to adapt back into society afterwards.

The A.T. Guide 2012 by David Miller 
This is the choice guide book for thru hikers. Miller keeps it up to date with which hostels, hotels, post offices, etc are still open, which ones closed, where all the water sources are on the trail, town maps, and much much more.

The Bible 
Just throwing that out there.  Nothing to do with the trail, but everything to do with the journey!

I have read a few other books, mostly just accounts of thru-hikes, but in my opinion, the ones I listed were the best.

Resources on the Interwebs:
You will find a lot more, but these are some that I have bookmarked.

REI, Campmor, Backcountry, Steep and Cheep, The Clymb, Gear Trade

Backacking Basics:
How to load a backpack
Adjusting the fit on your backpack
Cooking and recipes for the backcountry
Food for long distances

Appalachian Trail: overload of information
The AT distance calculator - great tool for getting distances between shelters and points of interests
AT weather - up to the minute weather conditions at the shelters
Backpacker Magazine's AT guide
The Appalachian Trail Conservancy
The AT Guide - links to buy the guide, but also has sample itineraries and gear list
Map - a pdf of the entire trail
Datto's AT Thru Hiking Tips - a little dated but invaluable info
Mountain Squid's How to Hike Guide - a compilation of valuable links in whiteblaze
Sample gear list
Sample clothes list

Blogs and Trail Journals from Past Thru Hikers:
5 Million Footprints - a blog from a 2011 thru-hiker