Have a good look in the between the door bellow & drum all the way round (pull the edge of the bellow away from the drum slightly). If you are lucky you may see a small article of clothing sticking out, if so see if you can pull it free with a pair of pointed nosed pliers while moving the drum backwards & forwards. If that fails you have 2 choices...take off the sump hose & fish it out, or take out the heater element & fish it out.
Mike, October 2009