Stumbled across a really good resource if looking for used hiking books, Thrift Books (
www.thriftbooks.com). Their business model is that they cull all the books from thrift stores across the country looking for the best books and then sell most of them for $3.79. So far I've picked up some out of print guide books by Harvey Butchart and Bob Martin along with a bunch of books on the Grand Canyon. A nice feature is adding a list of books to a wish list and then they will email you an alert that they have it, this morning picked up an elusive copy of "Grand Obsession" for $15.