Is God Just a Human Invention? Another book with a question for a title - but questions are good, and this book tackles about 18 of them that are being asked the most these days. Written by Sean McDowell and Jonathan Morrow, with contributions from a ton of excellent specialists, this book is a phenomenal resource and doesn't have to be read in any particular order. (an interview with the authors here)
Evidence for God: 50 Arguments for Faith from the Bible, History, Philosophy, and Science is another book loaded with great content - 50 essays! - with contributions from a ton of top-notch apologists. A close competitor with the previously mentioned book that happens to be a great resource.
On Guard: Defending Your Faith with Reason and Precision by William Lane Craig is excellent for personal study or group studies. Weighty material that is clear, precise, and put together really well. I'd give this to Christian young people in high school and college who want to strengthen their apologetics foundations. (review here)
And finally, here's the stocking stuffer of the bunch: Kreeft and Tacelli's Pocket Handbook of Christian Apologetics. The reason? Again, lots of material packed into a small book, organized and presented well.
All these books would be my top 5 candidates for apologetics books for giving this Christmas. Of course, you could always give them a Kindle and load it full of books. You can now also "gift" Kindle books to anyone with an email address (for reading on the Kindle, or the Kindle software - PC/Mac/iPhone/Android)
What books do you recommend?