A very interesting, but also shocking in its own way, site is http://www.trufax.org. Go to the information on Matrix 5; Val Valerian runs the site, but The Author wrote Matrix 5. I bought the Matrix Gold books which are extremely interesting, but also depressing in their own way. They are written by a person who has done a lot of astral travel in the last ten years. I don't agree with all of the information, but then I have never done astral projection and, perhaps, am not ready to receive all of the information. One needs always to be aware of what feels right to oneself because information coming from any other source other than our own Higher Self has been filtered in some way by the writer's own perceptions and life situations.
The Monroe Trilogy is also interesting. These three books were written by Robert Monroe, a broadcasting executive who suddenly started astral travelling.
These books go far beyond any religious discussion of our lives here on Earth.