Every once in a while I get a similar message from a new Mac OS X user: Help, I've hidden a window from an application, how do I get it back? Having freaked out the first time I accidentally hid a window, I know what that feeling is like.
Fortunately bringing back a hidden window is easy, if not obvious. Just go to the Dock, and click the application icon for the window you accidentally hid. For instance, let's say you accidentally hid a Safari window. Just go to the Dock, and click the Safari icon. Instantly your hidden window comes back into view.