Mastering Astral Projection: 90-day Guide to Out-of-Body Experience by Robert Bruce and Brian Mercer is exactly what its title suggests: a 90 day program by the end of which you will learn how to have out of body experiences at will. The program is based upon Robert Bruce’s excellent book on the subject, Astral Dynamics.
The book is also available in a voice guided version, which is called “Mastering Astral Projection CD Companion.”
This, unfortunately, uses the same cover art as the book, so many people think it is the same, but it is a totally different product.
It contains CDs with voice guided instructions for learning everything from energy work to OBE exits in addition to binaural beats tracks (like Hemi-Sync, but created with a different brainwave generator, see: bwgen.com).