FaithLife, producers of Logos Bible Software provides some of the best resources for Bible study available. They are the top of the line for digital Bible Software. To promote their product they offer free books on a regular basis. With patience, diligence and discipline, for no cost, you can develop a sizable digital library of quality. As you build your library you may want to check out the extra features offered by purchasing an upgrade. To start, you will be required to open a Logos account [LINK].