The link below will do an interactive search of the KU Library catalog to retrieve e-books on Central Asia topics:
http://catalog.lib.ku.edu/cgi-bin/Pwebrecon.cgi?DB=local&SL=none&Search_Arg=%22electronic+books%22+and+%22asia%2C+central%22&SL=None&Search_Code=FT*&CNT=25