Game Programming With Python
You can write whole games in Python using PyGame. See a list of other PythonGameLibraries maintained in this Wiki, or this list maintained on DevMaster.net. A full tutorial can be found in the free book "Making Games with Python & Pygame".
If you have an existing game and want to add a scripting engine to make it more flexible, Python is also a very good choice. But you'll have to learn about IntegratingPythonWithOtherLanguages.
Read Humongous Python for a case study.
Read Python game programming tutorial. Or if you need object-oriented design read Yet another game programming tutorial.
If you want to learn Pygame read this game programming tutorial series.
Two pages that are dedicated for python in 3d are Python 3D(py3d.org) and Python 3D Software
PyWeek is a bi-annual programming challenge that produces several great games.
Books
There's also some books that specifically cover game programming in Python:
"Invent Your Own Computer Games with Python" is a free, Creative Commons-licensed book on Python for complete beginners with no experience programming. Each chapter has the source code for a small game such as Tic Tac toe, Hangman, Reversi, and others. The final chapters provide an introduction to Pygame.
http://inventwithpython.com/pygame
"Making Games with Python & Pygame" is also a free, Creative Commons-licensed book that assumes a small amount of Python programming experience. It goes into more detail with the Pygame library. There is the source code for games such as Tetris, Connect Four, Simon, Sokoban, and others.
http://www.charlesriver.com/titles/pythongame.html
- "Game Programming with Python is about building games using Python. It deals with general concepts of game development and specifics that apply when using Python for game development. Some of the general topics include simulations, game architectures, graphics, networking, and user interfaces."
http://www.handysoftware.com/cpif
- "The author set out to write a book like the one he used to teach himself programming at age 12. ... This book has been successfully used by homeschooling families and public school teachers." The library and example code supplied with the book is also available for download.
http://eu.wiley.com/WileyCDA/WileyTitle/productCd-0470068221.html
- "Ever want to develop your own computer game? Learn the practical concepts of object-oriented programming for game design using Python in this easy-to-follow, content-filled guide. Whether you're a student, aspiring game developer, or veteran programmer, you'll gain skills as you progress from station to station in a series of clear-cut tutorials on different styles of games. The last stop will be a finished game program for you to show off."