Can anyone direct me to a book or commentary on Jewish thoughts on what happens after death, and the evolution of those ideas. I understand that Judaism is centered on how to live life, but from I can read is somewhat obscure or absent in discussing an afterlife. My Christian friends often asked me, what do Jews believe in after death?
You could try Journey to Heaven: Exploring Jewish Views of the Afterlife. It's on my to read list, but haven't gotten to it yet so your best bet is to read the amazon reviews.