I've finished up two different books in the last week or so. Let me share them with you. First, I found Preaching: Pure and Simple in a mailer from Cumberland Valley Bible Book Service. This book, written by British evangelical Stuart Olyott, is a helpful introduction to preaching. His characteristics of good preaching are helpful-- exegetical accuracy, doctrinal substance, clear structure, vivid illustration, pointed application, helpful delivery, and supernatural authority. In addition, his conclusion outlining his method of preparing sermons is good. This is a shorter, easy-to-read introduction to preaching. There are more extensive books out there. But the brevity of this book makes it one I might use with Karis interns in the future.
Second, Every Thought Captive by Richard Pratt was recommended to me by a good friend, John Divito. I had hoped for a bit better explanation of the holes in non-Christian arguments, how they are truly folly. Despite this, I think this would be a great book to hand to someone to introduce him or her to a presuppositional method of defending the faith.