L. Ron Hubbard currently has two books that are available.
Scientology Infinity — which is a book of daily drills that can be done at home and is perfect for the beginner — and veteran Scientologist alike.
The other being Infinity Series — a compilation of technological bulletins that are for the more experienced practitioner.
Unfortunately — due to several complaints by Bridge Publications — these books are currently no longer on Amazon.com. We are in the process of finding a fair and impartial book vendor — to offer these titles. In the meantime — you can submit an email and request a digital copy of either title.