One of the best books you can get for all your questions is The Appalachian Trail Thru-Hike Planner put out by the ATC. Follow this link as there are a lot of different editions.
Http://www.amazon.com/Appalachian-Tr...il+conservancy
It will cost you $10. If you can't afford it, PM me. Many veterans on White Blaze put it down because it can teach
them nothing. Even the reviews aren't so hot. Like a fool, I waited 6 months and this book could have told me pretty much everything about the trail. It tells the average temperatures each month at each region, average costs, mail drops, gear and there is a kind of workbook where you can plan everything. White Blaze can teach you a lot but not all in one place.
There is a group of us at my house who watch the daily AT videos. They can't be beat. Most of us like Loner20012AT videos. Go to YouTube and start with #1 and he is now on #97 or so and you will learn all about the trail. If you think you want to travel with a group, Fatherman's videos are probably what you would enjoy most, but both guys have done a fine job.