Lowell Green, who actually spent some time studying at Erlangen has written a book about the Erlangen school. Of course, much of what was written and argued for by these folks in the name of Confessional Lutheranism is quite problematic. Nevertheless, many of the thinkers associated with this school I have found quite useful and interesting down through the years. Notably, Theodosius Harnack, Werner Elert, Paul Althaus, Franz Delitzsch, and of course Herman Sasse. So, I encourage you to check it out. I just received my copy today.