for Taipei, Taiwan's Aerial image, I use
this one as whole taiwan
http://921farmers.cultureworld.org/image/TaiwanNo1.jpg
+
this one for more detail image
http://iws.csrsr.ncu.edu.tw:8080/JSP/CSRSR/homepage.jsp?UserId=guest
+
this one for very very detail image
http://addr.tcg.gov.tw/

http://www.globalsecurity.org/military/world/taiwan/taipei.htm
this one as black and white detail