I fear you may not find one. David Mullet is working on a book but that rather implies that it's still some considerable time away from publication.
I need a complete, systematic standard
tutorial for WIN32OLE ruby APIs.
How "complete", "systematic" and "standard" do you really need it to be? You have to consider that someone needs to have the motivation to produce such a tutorial, which would be a substantial piece of work to undertake for no reward; that's why a book is in preparation - then we can pay David for his expertise!
So we may need to modify your need to be more satisfiable by current reality: are there particular problem(s) you are trying to solve? Could you put some more specific questions here?