This week's book giveaway is in the Mac OS forum. We're giving away four copies of a choice of "Take Control of Upgrading to Yosemite" or "Take Control of Automating Your Mac" and have Joe Kissell on-line! See this thread for details.
As GWT auto-generates the pages, I doubt it can be used with anything else. Unless there are some hooks that they've added to allow this, that is. I wouldn't know as it is not a tool I'd consider using.