I have very little experience building software for Windows, and zero experience using the Windows API, but I\'m reasonably familiar with Python. How should I go about learn
Learning Win32 API is 5% of initial understanding of concepts and the patterns used and 95% of RTFM.
For those initial 5% the Petzold book is really good but I suspect that there ought to be some online tutorials which you can find in google as good as I can to find.
Really, once you get the hang of it it's really straight forward do to be able to do anything. Once you get there it would probably be time to move on to something better like QT and never touch Win32 API ever again. Nowadays no one really uses bare Win32 API for anything more than trivial due to the sheer overhead it involves and the extreme lack of comfort.