I'm beginner for the GUI programing using Tkinter, so who can tell me some useful sample codes which contains some useful codes.
This is what I used: Pythonware -- An introduction to TKinter.
I quickly switched to PyQT, though :)
Here are several video series on building python GUIs that got me started
If you learn best from video, Charlie, I recommend http://showmedo.com/videotutorials/video?name=pythonShawnTkinter1&fromSeriesID=58 ; if from books, http://www.manning.com/grayson/ . For a free online tutorial, I second bedwyr's advice -- and I especially second his (implicit;-) advice to use PyQt instead. (A web search for pyqt tutorial shows many pointers).
I found Thinking in Tkinter very helpful for getting my head around the concepts of GUI programming (notably, packing widgets inside other widgets, and binding callbacks to events).
Mark Lutz's tome Programming Python deals at length with Tkinter. The Introduction to Tkinter ( effbot.org) and Tkinter reference: a GUI for Python (John Shipman, New Mexico Tech) are good summaries of the major features. I have read that the Tk/Tcl manual is a good reference but that might be for later.
I just came across http://www.shido.info/py/python6_e.html which looks very handy