The following has been added to the Bibliographies Page at this site and to the Zotero Group for Ancient World Open Bibliographies.
I had the pleasure of spending an hour with the late Traianos Gagos at Michigan when I visited during my graduate school application, and those who knew him well will understand why I remembered him fondly even 15 years later. Among his many scholarly legacies is:
Papyrology
http://www.lib.umich.edu/papyrus-collection/select-bibliography-papyrology
A Select Bibliography of Papyrology
Traianos Gagos, Library and Dept. of Classical Studies, University of Michigan.
Copyrighted 1/11/96 but web page last update is 8/1/09; works seem to be pre-1996.
This is described as an introductory bibliography, broken out by areas of interest (abbreviations, chronology, epistolography, editions). Coverage is international and includes books and articles.
Ancient World Open Bibliographies 