python code for "add data" in ArcMap

Dear all,

System: Windows Vista
ArcGIS 9.3 Workstation
Python 2.5

I want to know any python code for overlay two shape files (A and B)(+ icon for add data) in ArcMap.
A is a world map.
B ranges from B1 to B100, including range maps of 100 bird species.
I want to overlay the world map with the bird species map respectively but not repeating the same thing for 100 times.
Thank you.