I used to be based at Odiham when I was in the RAF. Unfortunately taking private aircraft into RAF airfields is a bit of an admin exercise, even for a serving RAF officer. If your mate is stationed there, he might be better placed to make some of the arrangements on your behalf.
Regarding Hook airstrip, I have always taken a good look at it whenever I have driven past and would very much like to use it some time. My aeroplane is in the Piper Cub class (ie pretty short takeoff/landing distance required) and that strip looks seriously challenging to me: 250' powerlines, trees, motorway, short length etc. There's no way you could safely use it in a Cessna or Piper class aircraft.