Dizzyy,
In addition to the sources that Jessica pointed out, you can also click on the link up top of this page that says "The Main Page", here there is a list of resources, under Health, click Therapists and Counselors. From here you can choose from several countries/states/etc. This is where I found my therapist and have been very happy to have found him.
As Jessica mentioned, make sure they are experienced in gender issues and just someone who has read a paper on GID. My therapist is himself a transman, so I know that he knows what I am going through. There are many others here who have recounted experiences with therapists who are not really experienced with our needs and their experiences have been poor at best. So, understand that if you start with one therapist, you are not bound to her/him, you have the choice to not continue if you are uncomfortable/uncertain about them being able to help you. They are, afterall, there to help you, not you supporting them.
Also, if you don't have insurance, and money is an issue (like with me) try to find someone whose first priority is helping YOU and is willing to offer a sliding scale fee.
Well, I hope this helps and I wish you all the best in your journey. Please keep us informed as you move on (good or bad). I was a scared little puppy like yourself just a few short months ago, but, Susan's and my therapist have helped me immeasurably to find out a lot about myself.
Deanna