I think the following site should at least give you an idea of who operates what in the UK
Maybe you need to talk to Jethro himself
his emails is on the home page of his site
Or when you have the airline names contact Companies House in London
As not all airlines will operate all their aircraft under their own AOC again Jethros site can help as it lists on the righthand colomn who actually operates the aircraft
ie Jet2 operate under Channel Express
or Titan
http://www.jethros.i12.com/menu.htm
http://www.checksure.biz/
Hope that gives you a starter
G-I-B