The computer promises to revolutionize the study of our manuscript heritage by providing abundant new ways to examine and manipulate images. The best site for pursuing these topics in medieval domains is http://www.georgetown.edu/labyrinth/subjects/mss/mss.html
In addition, courtesy of Dr. Michael Gorman of Milan, whose translation of Bischoff's essays on ninth century writing schools has just appeared, a version of the map from that book showing the location of principal writing centers in Carolingian Europe.