esword is a free bible study software. I have about 12 bibles and several commentaries. Once you download and install ,there is a download link in the program window to download bibles and commentaries. You can also do an internet search for additional content. I found some premium content on the internet that I would otherwise have to pay for. Esword recently updated so old .bbl files don't work only the new .bblx files work. well worth the time. here is the link.
http://www.e-sword.net/
check out this site for free ebooks. they have a great theology section.
http://avaxhome.ws/ebooks
you may need to download winrar from download.com in order to decompress downloaded files. There is also a free ebook manager program that lets you read all ebook file formats like .epub and .mobi. The program also lets you convert files. it's called calibre.