A week or so back I mentioned one of the few full-length books (in English) that directly respond to Roman Catholic criticism of Martin Luther:
W.H.T. Dau, Luther Examined and Reexamined: A Review of Catholic Criticism and a Plea for Reevaluation (St Louis: Concordia Publishing House, 1917)
Copies of this book are extremely rare, or were rare. Within the last few weeks, reprints of this book have shown up on on-line used bookstore sites. For instance:
Now the prices are still a little steep: the cheapest goes for around $53, the most expensive up near $75. I'm not sure who's responsible for the printing, but whoever it was, thank you.
I already have my copy of this book (an original from 1917), but any of you that dialog with Roman Catholics about the Reformation will enjoy this resource.