What can I do to stop the pain?

Hello. I have been suffering from Plantar Fasciitis for several years. I had x-rays taken of both feet and per the doctor, my left foot is worse than my right but it is my right foot that is causing a lot of pain. It is has gone beyond waking up feeling like a gimp. It hurts just about all day and is especially annoying and painful when I am trying to sleep. I have to lay in one position all night to accomodate my right foot. The pain has centered in the middle of my arch and is a constant and painful condition. I have tried stretching exercises and was prescribed a boot but neither one has been any help. What are the best exercises or treatments available? Thank you.