Further to my post in questions....
Since Sept 11 I have flown loads with work (airline) and found that the majority of crews are willing to have staff on the jumpseat providing you have a staff ID and show a keen interest. Although what does differ is the cabin crew reaction to you asking. One said there was no way at all that I could ever fly on the jumpseat, but then came back 5 minutes later saying she was sorry because she didn't realise I was staff and said I was more than welcome.... And I haven't personally known any of the crew but they have all been more than welcoming, however you must be a staff member.
My first flight deck trip was when I was 14 MAN TFS with UKL on a 737-400, and still nearly eight years later, I was one of the best days of my life.
Since then I have flown on loads on jumpseat flights.... 757 767 737-400 md83 A320 BAC1-11 ATP J41. And all I did was write to the airlines..... but in my letter I explained what some of the instruments did eg "The HSI......" This got the attention of the base captain that the letter was addressed to.
Overall, what you have to remember is that pilots tend to a (slightly!) older version of wannabes. They know how hard it is to get in and they have also been young and keen too. Keep writing, even if it's just to ask for a day visit to the ops dept, it's a foot in the door. Best of luck!