There are not much information in .NET articles and books if you want to learn Window Messages (WM), you need to dig to various Visual C++ books and articles on pure Win32 Windows Programming (Not MFC) to learn these stuffs. The more you understand Windows, the more you will get to know Window Messages.
MSDN online has nice set of articles regarding this subject, but are pretty complicated for beginners.
windows messages
enablerbr
Caloroin
Spy++ is an invaluable tool for logging window message activity. It comes with Visual Studio (and possibly the Platform SDK, I can never remember).
Smith Sanders
but i`m not actualy get it fro there coz the wm message is too big..
RoMo
What do you mean by the message being too big
Carter33
MSDN online has nice set of articles regarding this subject, but are pretty complicated for beginners.
Catch22 is a good site to start:
http://www.catch22.net/tuts/
After you're done with the tutorials, I suggest to you look at the links section, it has a list of other useful Win32 sites.
Regards,
-chris