BUY the books and learn from them.You'll NEVER get a better work outside of the Holy Bible.
Francis Schaeffer systematically proves the existence of God and Christ. He also dissects the major philosopical and religious schools of thinking and explains their faults when faced with reality. This is not intended to be a philosophy book, however I would question the intellectual relevance of anybody who would say Francis Schaeffer is a not brilliantly educated in the matters of worldly philosophy. Try reading "How Should We Then Live", "True Spirituality", or "Genesis In Space and Time" for further Schaeffer reading. An excellent book for the neophyte Christian, or for an adolescent is "How to be a Selfish Pig", also by F.A. Schaeffer.