I highly recommend David’s book Life Extension Express if you’re interested in getting started in extending your life. It’s very easy to read and understand with a very clear description of the 7 steps you need to take to extend your life. It’s a great starting point for your journey to extend your life. The most important thing about the book is that it motivated me to change some of the behaviors that would decrease my lifespan. The author also lists 100 rules to live by which in itself is worth the price of the book alone.
On the negative side it could use footnotes and it may not be useful to people who are already familiar with the basics of life extension.