OCD-UK is the national charity for OCD sufferers. They have some great resources on how to talk to your GP about your OCD, what help is available for you, as well as some self-help resources.
Mind is a mental health charity, who offer support, information and guidance on a variety of mental health issues. They have some particularly great resources on how to help family/ friends understand what OCD is.
The Mental Health Foundation is an all-round great website for all things pertaining to mental health, including news, blogs and podcasts.
https://www.mentalhealth.org.uk/
OCD, the PhD and Me 