So this in article we are not interested as much in a clear cut disciplinary distinction between, for instance philosophers, theologians or literary writers, as we are in the use of faith and reason in the way described above. In other words in how they have accounted for the hope in them (1 Pet 3:15).
In this tradition two giants stand out right away: St Augustine of Hippo and St Thomas Aquinas. They are not the only models by far, and they are not opposed to each other, as Thomas, who is posterior assumes Augustine in his own thinking though sometimes reaching a different perspective. Philosophically Augustine relies more on Plato, whereas Thomas, without ignoring Plato draws much more from Aristotle's works just made available during Aquinas's life. There might even be an "temperamental affinity" between Augustine and Plato on the one hand, and Thomas and Aristotle on the other.
To be sure there are, before and after Augustine and Thomas, many great and original Christian thinkers up to this day who continue to give reasons for their faith. But in a way the two giants are so important that it is impossible to ignore them, and consciously or unconsciously to lean more towards one of them or the other.There is abundant literature about both of them, and the challenge is not to find information but to discern it. Here the criterion used for this selection follows the goal outlined in the initial paragraph, at an introductory level.
With that in mind, here is a recent and short article about St Augustine. If you wish to approach one of his many works check this English translation of De Civitate Dei ("The city of God"). Try for instance reading Book 8 or Book 19.
For St Thomas read this also short and recent article. One of his works that exemplifies this use of reason to account for our faith is the Summa contra Gentiles (roughly a "Compendium against the Errors of Unbelievers". Try reading chapters 2 or 4 to start with.
Contemporary models leaning more towards de Augustinian tradition include Josef Ratzinger, theologian, cardinal and eventually Benedict XVI. See this short address of his on faith and reason given at Regensburg. Check this article by Tracey Rowland on him. Cardinal Robert Sarah in his new book "The Day is Now Far Spent" (read a good review here) heavily relies on Ratzinger too. Another very influential Catholic thinker in this same stream might be Saint John Henry Newman, who was recently referred to as "the Augustine of our times". 
On the Aquinas side names that immediately come to mind are Josef Pieper (wonderful article about him here), Etienne Gilson (find here a wonderful bio), Jacques Maritain (see bio at a centre that bears his name), Cornelio Fabro (see bio and works on a dedicated website) and Karol Wojtyla, later John Paul II (see an article about his grounding in St Thomas).These are only a few names, good points of reference for anyone who wishes to harmoniously combine faith and reason. Other examples are Gilbert Keith Chesterton, Clive Staples Lewis, Elizabeth Anscombe and Peter Kreeft.
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