I really enjoyed both books by Bill Walker I've read. One is Skywalker: Close Encounters on the Appalachian Trail and the other is Skywalker: Highs and Lows on the Pacific Crest Trail
Others I've enjoyed:
Hiking Through: One Man's Journey to Peace and Freedom on the Appalachian Trail by Paul V. Stutzman
AWOL on the Appalachian Trail by David Miller
Becoming Odyssa: Epic Adventures on the Appalachian Trail by Jennifer Pharr Davis
That should give you a starting point. I would recommend Jon Krakauer too, as you mentioned. Into the Wild is one of my favorite books, but Into Thin Air is probably his best work. I've also read a couple of his others that were great...I don't think you can go wrong with Krakauer. Another favorite everyone has read is A Walk in the Woods by Bill Bryson...and for good reason. That book is outstanding.
Thank you. Yes, Bill Bryson is bound to be a good read. I read a great book by him, very impressive that he could write it as a layman: A Short History of Nearly Everything. I've seen AWITW recommended before, I'm going to read it now, get it from my library, heaven knows they have it.
All I know of the Appalachian Trail is what Cheryl Strayed said about it in Wild, that it's several times more traversed than the PCT, and as such is not nearly the adventure. When Cheryl came to that water tank that just couldn't be empty but was, well, you know what I mean.
After the Bryson I'll read some Krakauer.
The other adventure writing I remember reading was Jack London. Also, Herman Melville.
London was very much an adventurer in his younger days. Later, I think he became a sort of corrupted version of himself.