In case you haven't seen it before, this site, http://rohland.homedns.org/at/at_menu.aspx lists road crossing and trailhead info for the entire AT.
What makes this site exceptional IMO is that it not only gives excellent written directions but also includes a google map and google streetview so you can actually see the trailhead so you'll recognize it when you get there.
Also offers a hiker related parking safety feature which would really be cool if more people used it.