I believe there is a package you can request (at least I did) from SSPX which has a number of books on Vatican II, Archbishop Lefebvre, and SSPX. I personally like their Frequently asked Questions book.
If you want to have a firmer understanding (for the most part) of the traditional Catholic movement, get The Resurrection of the Roman Catholic Church, by Griff Ruby. I enjoyed this book a great deal, and it helps clarify a lot of basic questions.
Problems with the Prayers of the Modern Mass, by Fr. Anthony Cekada, ex-SSPX, ex-SSPV, now independent priest, published by TAN, and also Problems with the New Mass by Rama P. Coomaraswamy, also from TAN.
What went wrong with Vatican II? by Ralph McInerny (of Fr. Dowling fame) is tedious but a good ground floor work by a Novus Ordo conservative. The Rhine flows into the Tiber is an old classic.
The SSPV is little strict for me, but I give them credit for their scrupulosity in doctrine. Bishop Kelly once did speaking tours for the John Birch Society, and wrote a book based on those talks I believe.
Of course I could name tons more, and you can message me if you want more, but I think these will keep you busy for a while!
