There is a list of upcoming Python-related events at http://python.org/Events.html and Python-related Conferences and Workshops at http://python.org/workshops/.
Conferences
InternationalPythonConference is the biggest annual Python-related event.
PyCon is a low-cost user-driven conference.
EuroPython started in 2002 and had a successful sequel in 2003.
- ["PythonUK"] ...