Yea, done this myself a while back.
Best way, call the HQ front desk. Ask for the flight/aviation/transportation department (whatever they call it). Most receptionists will give you their number. Then call the dept, most likely you'll get another receptionist. Ask for the chief pilots name, email and any other reasonable contact info. Most companies I've talked to are more than willing to give out this info.
I know this sounds stupid, but it works. Especially, if you don't have any contacts.