I only have two of his books in dead tree format, the two published by Regent College Publishing, but I can tell by the reviews and stature of the publishers that have published his works that several more by him are in order for Faithlife/Logos than the three that are already available (Pocket Dictionary of Apologetics and Philosophy of Religion; and Faith beyond Reason: A Kierkegaardian Account and Why Believe? Reason and Mystery as Pointers to God in pre-pub).
Philosophy of Religion: Thinking About Faith (Contours of Christian Philosophy) by C. Stephen Evans and R. Zachary Manis (IVP, 2009)
Kierkegaard: An Introduction (Cambridge University Press, 2009)
God and Moral Obligation (Oxford University Press, 2014)
Natural Signs and Knowledge of God: A New Look at Theistic Arguments (Oxford University Press, 2012)
Kierkegaard's Ethic of Love: Divine Commands and Moral Obligations (Oxford University Press, 2004)
Kierkegaard on Faith and the Self: Collected Essays (Baylor University Press, 2006)
Søren Kierkegaard's Christian Psychology: Insight for Counseling and Pastoral Care (Regent College Publishing, 2014)
Preserving the Person (Regent College Publishing, 1994)