Don't overlook the power of letters to the editor of your local paper. That is about cheap and grassroots as you can get.
At the other extreme, a national organization governed by a Board of PWP overseeing a staff of non-PWP would allow the former to set policy and the latter to do the work. Also, setting a time limit on Board membership would force a solution to the problem of each of us having our limits.
If something shows signs of getting off the ground, I have a domain name I would be happy to contribute - "ParkinsonsOnline.net"
There is one caveat to that offer, I also have "ParkinsonsOnline.org" that I am (slowly) developing myself for educational purposes and want to keep. You are welcome to visit and see the tack I am taking, just wear your hard hat.
A possible video might be a series of short video segments (say 3 to 5 minutes) strung together in which individual PWP talk of what we face. An outline of critical points as a starter would be a good idea and then selection of the individual segments that best made those points. Put it on the website, Youtube, etc with copyright that allows free distribution. Maybe even make it such that a neuro could give a copy to the newly diagnosed to help them come to terms with PD. Actually, there is room there for three or four different ones. They could be an excellent way of spreading the new group's name around as well. Just splash the URL across the bottom of the screen all the way through.