One site i didnt see mentioned is www.winprog.org they have a huge tutorial on win32 programing with C, but can very easily be applyed to C++

I learned C in College but not the whole language because I was an EET (electronics Enginerring) sutdent. But we only made DOS applications, and small ones at that. So I was disapointed as I wanted to make profecional GUI apps that everyone else was makeing. So I found the tutorial at www.winprog.org and that gave me the start I needed.

I would recomend you get a hold of the latest version of the Win32 programers refernce. You can grab a copy here http://www.cs.virginia.edu/~lcc-win32/ or frequently make visits to MSDN (microsoft development network) msdn.microsoft.com

However the compiler in the link for lcc wont compile C++ so be aware of that, but the Win32 documentation can be downloaded there.

Mostly if you know C++ already then Win32 will be prity simple.