Annie, 
Are you married? If so you should discuss your fantisy
              with with your spouse or partner. I am married and would be happy if
              my girl wanted to do something like that but would want to know about
              it first. 
I have been to a swingers party before. If you are not
              invited you will be seen as an outsider and not well received. Its
              best if the hosts know you and can introduce you around to
               brake the ice.  
Good luck in your quest to enjoy the
              nectur of the gods!
              
