This first post, I'd like to list a few books that I feel are especially noteworthy for over 1.0 COP systems. I know from hands on actual building experience that this information is valid... it just plain works.

Secrets of Cold War Technology by Gerry Vassilatos
This book is worth getting just for chapter 1 on Tesla. This single chapter is probably one of the most valuable complilations of information on Tesla and what he was really doing in plain and simple terms. It goes into longitudinal impulses and how these differ from transverse waves. All pulsed DC systems that are over 1.0 COP such as John Bedini's systems, Stan Meyer's water cells and other impulse systems are utilizing longitudinal impulses most likely. This book is a must have for anyone that wants to see what Tesla was really doing.
Amazon.com: Secrets of Cold War Technology: Project HAARP and Beyond: Books: Gerry Vassilatos

Bedini's Free Energy Generator by John Bedini
This book from 1984 is the old school book written by John himself about a unit that is over 1.0 COP. It is easy to build and is very straight forward. It uses some older terminology to describe what is happening in the batteries but still holds true today. A valuable piece for any researcher and builder.
Amazon.com: Bedini's Free Energy Generator: Books: John C. Bedini

Free Energy Generation Circuits and Schematics by Tom Bearden and John Bedini
Contains the original 1984 publication, many color pictures and illustrations, and the 100 plus page Provisional Patent Application that was originally filed in 2004 (not shown to the public). This treatise holds nothing back, and includes virtually all they collectively know about negative energy. Included are circuit diagrams, oscilloscope traces, the works!
Amazon.com: Free Energy Generation Circuits & Schematics: Books: Tom Bearden,John Bedini

Various books and videos by Peter Lindemann
Check: Electric Motor Secrets - revealing Bob Teal's Magnipulsion Engine
Product Information and Ordering from Free Energy Website - Edwin Gray, Nikola Tesla, and Dr Peter Lindemann

Energy From the Vacuum by Tom Bearden
THE BIBLE for over 1.0 COP systems
Very technical with tons of references
Table of Contents

Energy From the Vacuum Documentary series
Energy from the Vacuum A Documentary Series

Synthesis of Matter by White Dragon Press

Just gotta put in a plug for my own book:
White Dragon Press

If you goto White Dragon Press™ | Aaron Murakami you can sign up for the mailing list and you'll be notified when it is available. Some people have mentioned it is like a Bearden for Dummies book. In simple terms that virtually anyone can understand, it goes into what the virtual photon potential is, what a dipole is, the difference between open and closed systems, a seamless model of gravity, inertia, mass, light speed, time, etc...

Basically, it is a Unified Field Philosophy for the general public that anyone can get. Should be available sometime in May.