A newsletter:

http://www.epda.eu.com/pdfs/epdaPlus/issue_03.pdf

Link from the magazine:

E_Gym
Electronic Gymnasium - Gymnastics for patients with Parkinson's Disease

http://parkinson-italia.info/e_gym_uk/

The audio isn't great, but it's useful. Example:

http://parkinson-italia.info/e_gym_uk/uk01.php