There was a rather good RPG maker a friend forced me to download at one point. I took a look but it all seemed like too much effort ( that is, if you're serious ). I could try and find out what it was called if you want.
It depends if you're thinking RPG in the zelda/pokemon sense or in the Indiana Jones and the Fate of Atlantis/Sam and Max sense cause there's a large number of - reasonably good - SCUMM editors out there.