There is no such layout by default and I have tried getting the one available here (http://www.kaufmann.no/roland/dvorak/) and it doesn't work with Windows. So is there any way I get the DVORAK layout on Windows?
From the Control Panel select Language and then Options:
In the Input method select Add an input method:
From there you can select the DVORAK R or L keyboards
You can use the Microsoft Keyboard Layout Creator to create any keyboard layout you want. It even contains DVORAK layouts to get you started.
Click File → Load Existing Keyboard...