Varii Scherzi di Sonate, Libro 4 (Corbetta, Francesco) has just been posted on IMSLP:
http://imslp.org/wiki/Varii_Scherzi_di_Sonate,_Libro_4_(Corbetta,_Francesco)#IMSLP343688 — R To get on or off this list see list information at http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html