Hi Garth
Welcome to the forum.
You might want to have a look at the following FAQ which explains where everything is;
www.benefitsandwork.co.uk/guides-for-claimants/faq/forum.
I am not aware of an email address to start of your claim for PIP, if you are unable to contact DWP yourself then you will need to have someone with you who will be able to do the talking although they will ask you to confirm details.
You could contact your local Welfare Rights Organisation;
advicelocal.uk where they can take all your circumstances into consideration when giving you advice and even help start the process.
Gary