One reason you may be having difficulty is that unlike some languages (C++/Java) object-orientation is not a be all and end all in Python, in fact you could work with Python for a long time without really 'doing it' at all (well other than calling methods/properties on existing API's). Having said that here's what I would suggest ...
Could do worse than this : http://www.diveintopython.net/object_oriented_framework/index.html and this http://docs.python.org/tutorial/classes.html read together. Judging by your question this is a probably a little advanced for now but you could bookmark it for the future: http://www.catonmat.net/blog/learning-python-design-patterns-through-video-lectures/ Here's the corresponding PDF to go with the video: http://assets.en.oreilly.com/1/event/45/Practical%20Python%20Patterns%20Presentation.pdf -- http://mail.python.org/mailman/listinfo/python-list
