I also suggest that you add Catechism of the Catholic Church to your collection of source material. You can also read it online here
If you are feeling saucy, you may also want to check out these books by Robert Sungenis:
Not by Scripture Alone: A Catholic Critique of the Protestant Doctrine of Sola Scriptura
Not by Faith Alone : A Biblical Study of the Catholic Doctrine of Justification
Not by Bread Alone: The Biblical Evidence for the Eucharistic Sacrifice
Sungesis's books are wonderful, exhaustive defenses of Catholic teaching. Each book tries very hard to be non-polemical, and succeeds IMO. They also contain critiques, in the classical sense, of classical Protestant teaching and modern Protestant writings, including Geisler. If you love Truth, then I cannot even begin to recommend these books enough.
Pray for John Paul II
Yes, I use the catechism, too. It's on the newadvent.org website along with the catholic encyclopedia and other documents. Actually I use two other sources that I left out also: A book called "Who's Who in Christianity" (publisher: Routledge) and the Vatican website. So, in all, I'm learning from only one source written by a protestant; all other sources are catholic. So you guys can't group me with the "Chick" crowd!! Thanks.