There are 2 tools that I know of: RapidDoc and Project Documenting Machine (PDM).

RapidDoc costs money ($99, IIRC) and I do not think it is being supported anymore. It will document an entire project or the constituent pieces, you choose what to document.

PDM is free. Google it and then download the Zip file to your PC.

Contact me diectly if you have any more questions...

-RW-