It's so exciting that so many people have got their referrals! Assuming that the 'gynae appointment' you refer to are the same as fertility appointments, then my experience a couple of weeks ago was that they give you and your partner a reeally long questionnaire about general health, lifestyle, and also cycles.
Then they gave me a form for some more blood tests, sold me an £80 AMH blood test, did my height and weight, did an internal scan and some swabs, and gave my husband a sperm test bottle to do another sample in a couple of months. Oh, and they also gave me a form to hand in to reception to request a HyCoSy (HSG).
Hope that helps! Oh, and in terms of what to ask, be aware of your options and ask for them... e.g. in terms of luteal phase, if you want more 21 day bloods, or follicle tracking for a month, then ask for it. I felt like if I hadn't have asked she would have sent us away for 2 months until the HyCoSy was complete and DH latest SA was back.