Alternatively, if you don't manage to find any contact details, you can contact NATS HR who can help with contact details.
It might also be worth visiting an en-route centre if you have time - most people end up working as an area controller rather than at an aerodrome, so it might be useful to see what you're more likely to do if you're successful.
Plenty more info on the interview thread at the top of this forum - just ask and people will try and help!
Good luck...