I haven't had much involvement with the GP since my diagnosis, the Gp acted as a middle man so too speak tween me and neuro or PD nurse when they built up my current dose but that's it since the start of the year.
Your dad's neuro could and should of referred him too his local PD nurse.I'm not sure if there is any other avenue of being referred other than by the Neuro, it seems gaining appointments with them can be difficult, but you could try getting hold of the Neuro's secretary if they ever answer the Phone.
Your local Gp practice should have a mental health worker attached too it, which will lead on too the well being service, which is usually in the first instance a telephone discussion too discuss their need's. I suppose the best way too move things along would be requesting a home visit from your Gp in your own environment if you cant get anywhere in theirs.
I suppose you could also use the Parkinsons help line who should put you in contact with the parkinsons support worker.