Mouse operations?

Where could I find a good source for information on mouse interactions?

???

In what context?
For windows, look up the mouse input reference. Start at any function like SetCapture and go to the overview using the links at the bottom.
Or go to
MSDN Library -> User Interface Design and Development -> Windows User Interface -> SDK Documentation -> Windows User Interface -> User Input -> User Input -> Mouse Input

I wonder if there is any logic behind the new structuring of MSDN :rolleyes:

For DirectX, look up the DirectInput documentation.