Hello squashmypuffies
It all depends on whether you want to go NHS or private. However, I would always recommend you see you GP in the first instance. GPs are generally quite ignorant on Gynaecomastia - not deliberately so, but they just see so few people coming to them about it. I was the first patient my GP ever had regarding gynaecomastia.
Explain to your GP your concern. He or she will probably want to have a look (though many would not really know what they are looking for). Tell your GP (if they don't say it first) that you are aware that Gynaecomastia is sometimes hormone related and would like a referral to an endocrinologist or urologist to run some hormonal checks just to rule out any underlying cause. THIS IS IMPORTANT - if there is an underlying cause (such as hypogonadism - low testosterone) there is the possibility your case may get worse or return after any future surgery.
If you are thinking about NHS surgery, you need two things. Firstly, a sympathetic GP. Secondly you need to explain how this condition effects you PSYCHOLOGICALLY. If you turn up to you GP and say "I don't like my chest, can I have some liposuction please?" you'll be laughed out of the surgery as this would be deemed to be a cosmetic need only.
You need to explain how it effects your daily life, such as having to make sure you wear loose and dark clothing ALL the time; walked with hunched shoulders to 'hide' your breasts and often have your arms folded in front of you. Say how you NEVER take your top off in public or take holidays to hot places; how it effects your sex life that you have no confidence with sexual partners. These are good grounds for having corrective (rather than cosmetic) surgery.
If after this you do not get the support you need from your GP, go to the surgery reception and make an appointment with another GP (it's no guarantee, but I'd feel more comfortable with a younger female GP if there is one at your practice - they are often more understanding). If there is not another suitable GP at your current practice, switch to a different (larger) one, you have the right to do this.
If you go NHS, it is not you that contacts the surgeon - it's your GP. The surgeon's secretary would then write to you in due course. If after the initial consultation with the surgeon, you are not happy (because you don't think he or she is experienced enough in male chest reduction procedures for example), go back to you GP. It's your right for to a re-referral to another surgeon if you and your GP agree that the first choice was not the most appropriate (not a lot of people know this!)
If you intend to go private, still do all the initial GP thing - endo/urol test etc. You then need to make an appointment with two or three surgeons for an initial consultation. You simply pick up the phone, ask for the secretary of the relevant surgeon. It's NO DIFFERENT to calling reception of your own GP. All you need to say is "Hello, I'd like an initial consultation with Mr X (all surgeons are usually 'Mr') sometime soon please. If you are asked for what kind of treatment, you are not obliged to say, but it's no big deal to just say "regarding male chest reduction surgery." That's it. An appointment will be made and you should be advised of the fee which is usually around £80-£120.
As for 'what kind of surgery', this depends of the preferred technique of the individual surgeon. Most go via the areola - the edge of the larger brown area that surround the nipple. A crescent cut is usually made here and the surgeon cuts out the offending glandular or breast tissue. Following this, liposuction of fat is usually indicated and removed from here. Scarring is a possibility, but with modern techniques, they usually fade very well over a few months.
More recently, but less used is through an incision near the armpit crease. The same work described above is carried out, but in this alternative place. I had this surgery performed on myself in January this year. the scars are about 1.5cm long, but not noticeable unless pointed out. They will continue to fade over the coming months. It's not really so much where or how the surgery is performed, but more to do with the skill of the surgeon and your body's ability to heal.
Everyone feels nervous about that first call. Everyone feels really anxious on the first initial consultation - but remember, these guys do this for a living and whilst they are highly skilled and want a high level of patient satisfaction - you are just the next piece of meat for them to butcher up!
Hope that helps. Feel free to message me if you have other questions.