There is several implementations of contact selector.
libempathy-gtk
Usable in C programs.
In python, how to get the Connection from EmpathyContact?
Contact Selector
In Python. Sources:
http://github.com/zhangsen/contact_selector/tree/master
Used by a gnomes-games branch:
http://git.gnome.org/cgit/gnome-games/log/?h=sudoku-tube
pyhalebarde's contact selector
The game pyHalebarde has its own contact selector: