I know you're not supposed to, but my favorite way to choose a new book is by looking at the cover. Sometimes it works out and sometimes it doesn't. I recently found out about The Book Cover Archive, and have been spending a lot of time browsing through the pages of covers they have on file.
p.s. The Catcher in the Rye is my favorite book of all time. I tend to read it all the way through at least once a year, and sometimes when I'm bored or in the mood I'll pick it up and flip through reading snippets of chapters here and there. My copy looks like the one on top - though doesn't look nearly as nice. I like that cover, but for a long time (like years) I've wanted to have a copy with the cover on the bottom as well. I've come close to buying one on several occasions, but always stop myself because I feel silly buying a second copy of a book I already own.