"The Didache" also called
"The Teachings of The Twelve Apostles"
Other than the 66 books of the Bible "The "Didache" is probably the oldest writings of the early Christians dating back to the first century. It has been said by those who have studied the early Christian writings that some of the Apostles were alive when this statement of beliefs was first wrote down. Because different heresies have entered into the Church over the centuries it is important to know what the earliest Christians believed.
E-Sword has many free ad-ons like dozens of Bible versions and several different languages, many commentaries, dictionaries all free. In addition to the free ad-ons there are reasonably priced products. Print out your own Bible studies.
Download the complete five year study of the Bible in MP3 audio format by DR. J Vernon McGee. This is not a verse by verse reading of the Bible but an insightful commentary. The only copyright restriction is that you got it free, you give it free. I have often put complete books of the Bible on a single CD and listened as I drive.
Do you want more than a superficial understanding of the pre-trib rapture point of view? The debate is much deeper than you might think!
Liberty University has an online archive of papers in a downloadable PDF format authored Dr. Thomas D. Ice. Some of the titles are; "Premillennialism, and the
Post-Apostolic Fathers", "A Brief History of the Rapture", "Yet Another Pre-Darby Rapture Statement", " Dispensational Hermeneutics", " Ezekiel 38 & 39", in total there are 50+ different titles.