I have a british passport and I am a british citizen

Bill, you need it to visit PRC. If you apply for it in Toronto, it charges 85 pounds or so for the entry permit and you also need to pay the service fee. You should contact with the CVASC in Toronto and confirm how much exactly the fee is.
If you go to PRC for tourism purpose, the required documents include your passport and copy of its data page, a passport-style photo and the application form, accommodation booking record and round trip air tickets as well as the downloaded and signed declaration. It usually takes 4 working days to process the application.