Firstly i'd just like to say it's brilliant that you are supporting your gf.
Esther is correct to say you need to choose between NHS and private treatment - NHS is much cheaper but there's a lot of waiting, you have a lot more control privately but it's expensive. A list of practitioners can be found in the following thread - see "Clinics":http://forum.transgenderzone.com/viewtopic.php?f=12&t=1220
Something else I would really recommend your gf do if she wants to do something tangible is to start hair removal - electrolysis on the face takes ages and it's much easier whilst still presenting as male!
It would probably also be beneficial if you or she registered on the forum, joined in the discussions and start a blog (these are hidden from you at present) as this will help to provide direction and encouragement. Being trans is a very lonely business and having others who are "in the know" to chat to is priceless.