http://www.bloomsbury.com/us/series/outstanding-christian-thinkers/?pagesize=100&orderby=1
This series includes books like:
- Aidan Nichols on Yves Congar
- Andrew Louth on Denys the Areopagite
- Avery Dulles on Newman
- Benedicta Ward on Bede
- Brian Davies on Aquinas
- C K Barrett on Paul
- Rowan Williams on Teresa of Avila
It is fairly ecumenical; you'll also find volumes on Calvin, Bonhoeffer, Kierkegaard, Barth, Niebuhr, Weil, Tillich, Bultmann, Edwards...
There are many more out-of-print volumes that won't show up on that link. Most can probably be found through http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Dstripbooks&field-keywords=%22Outstanding+Christian+Thinkers%22.
