I live in a smaller mid-weatern city,
one not noted for its cultural aspects, but our library has most of Maugham's works and recently bought a 10-cd sets of The Razor's Edge. I am on cd #5 of the set now, but I have read the novel a few times as well.
If you want to buy on-line, try Abe, Alibris, or Biblio. I have had better luck with these than Amazon.com.
I don't think Larry was shell shocked,
as Plain Jane says, but wondering what it (life) was all about. Larry was, after all an aviator, not an infantryman, who would be more susceptible to shell shock. In the episode where Larry tells of his Irish friend, a fellow aviator, dying and not realizing he was going to until near the end, I think Maugham tells us all we need to know about Larry's war time experience. I don't think anyone can know what it was like to fly one of those glued- together WW1 aircraft which spit out 50 calibre machine-gun buulets, sometimes shooting off their own propellor if not properly synchronized. I wouldn't call Larry burnt out, but rather questioning his pre WWI values.
I do not think Larry was shell shocked or burnt out,
perhaps war weary. All of his friends in Chicago felt that Larry was suffering from what he had experienced in the war, and that he would eventually come around. That is, he would get back into the swing of things, get a job, and ride on the post war prosperity. Larry, however, didn't want this. Rather than suffering from the common elements of battle fatigue, he was suffering from having his prewar values destroyed. This is why I feel Maugham gives the reader enough to go on. Larry wasn't, as Graham Greene said in his own title, a Burnt-Out Case. He was in search of a new set of values. That is why he couldn't marry Isabelle and go back to Chicago. Telling more of Larry's war experience is unnecessary. He tells all when he is asked by Maugham what he wants to do and he replies, "Loaf, just loaf."