Sorry, I can't remember right now how I exactly did it (some time ago), but depending on what you want to do, the masking tools might be of help for you. Paint a mask on the figure (easier than a selection), then fill the remaining area with the filling tool with white (the figure will be protected by the mask). The white part, if I remember it right, can be turned transparent without changing the opacity of the masked area. The selection by the magic wand will work also (and easier than before masking), you can then invert the selection... I don't know HOW I mangaed this, but once I was able to change the mask into a selection (I was playing around, so I can't reproduce what I did, but maybe it will help you...).