Right, this is for UK-based guys...

My gp is kind of rubbish and has not done much for me regarding helping me transition, but can he prescribe me t? Ok I'm only 17 but I've had 5 months of therapy and a consultant psychiatrist diagnose me with Gender Identity Disorder and told my gp of this a year ago.
I have an appointment with him tomorrow so would he be able to prescribe me T and if so what dosage would be appropriate?

Cheers 

if you are going to the gender clinic, i think you can only get the letter to say that you can go on T to the GP...So i dont think you can ask for one i think you will need a letter for it.

I have not been there my self, yet, but i have seem to see people on there from the uk, saying that they need to go though with the people at the gender clinic and then get a letter to go on T.

I don't know what a legal adult in the UK is, but some GPs are cool with prescribing their patients T. So if you're in charge of your body(according to the law) and your GP has fair knowledge of T, I'd say he could prescribe it to you.