Airlines don't use a 'company frequency' when talking with ATC - they use the published frequency that they are told to use for the specific phase of their flight - ground movements, departure, areas and altitude, descent, approach, and ground again - sometimes different frequencies for parts of the same airfield.
'Company frequencies' may be used by an aircraft to talk to their home base operations office, but it'll probably be out of radio range. ARINC provide a means to contact home base and their frequencies are well published. All reasonably sized airports will have handling agents for terminal operations, refuellers, catering, cargo etc but they are usually all organised by the operations agent for the airline. For instance Air NZ here handle Qantas, JetStar, Virgin, Mount Cook and others that pass through daily - they just call up on the operations frequency who arrange everything.
Instead of scanning through a whole load of frequencies, pick the departure frequency for your local airport and just listen that for a bit. You'll hear a flight number with instructions and the aircraft reply - you may hear ATC give him a hand-off to another frequency which you can follow and track the aircaftt until he is out of range.....
Hope that explains things a bit.
Cheers - Martin ZL2MC - Palmerston North
Last edited by majoco; 01-30-2014 at 7:02 PM..