Howdy...I recently started using my D-20 again after a few years of hibernation (the keyboard, not me), and I'd like to add some more sounds to it -- specifically organ & piano patches that are better than factory sounds. I've searched around on the net, but haven't been able to find anything that gives instructions on what kinds of files I need, how to load them in, etc. I apologize if this has been asked and anwered before...but can anyone point me in the right direction?