Hi anon85, maybe your GP can refer you to one? I can't remember how the NHS system works (and I never had mental health care while there) but I believe your GP can be a starting point in referring you.
That said: this is what I did where I live. I got my referral, but find it a difficult institution to manage. You can't call or e-mail your therapist, timing of sessions are limited to bang-in-the-middle-of-a-day which makes it hard to be discreet at work - but this may well be different in the UK. At least I hope it is!
Thanks. I felt really threatened and intimidated by the setup the NHS uses, as I have deep issues going back into childhood, and horrible memories of anorexia and psychiatrists and what my child mind interpreted as abuse. There are power issues, I have enough trouble going to a GP for athletes foot and being made to feel like something that shouldn't be walking the face of the earth.