You might want to take a look at
wxPython. It's a great GUI toolkit for Python, and it even happens to be Guido Van Rossum's favorite. I personally prefer wxPython to the other available options, but really you should just try it out and see if it tickles your fancy.
If you looking for an IDE to develop your python programs in (and a good example of wxPython in action), then you might want to take a look at
Stani's Python Editor.
Hope that helps!