Hello Paulz, you could try the 'reward system' for you and your daughter.
Sit together and make a list of rewards you would like, starting with small things (not crunchie bars) and ending with something special (like a big day out to a theme park, or whatever).
Once you have found an NHS dentist (good luck), don't make an appointment straight away. Firstly, just get in the car, drive to the dentist, park the car, wait a few minutes, then drive off to get your 1st reward.
Next time, you could phone and ask the dentist if it would be ok to sit in the waiting room for 5 minutes before leaving, and then go and get second reward. You can build this up with as little or as many trips to the carpark etc and rewards, until you are ready to have your check up and then go get your prize for being brave!