Here are a few available .net/.com domains that you can get now, w/ # of exact match searches per month:
appointmentletter.net - 9,900
appointmentcard.net - 1,000
salonappointmentbook.com/.net - 1,000
appointmentremindersoftware.net - 1,000
appointmentletters.net - 880
appointmentpower.net - 880
salonappointmentsoftware.com/.net - 880
appointmentreminderservice.net - 880
onlineappointmentscheduler.net - 880
appointmentsystem.net - 720
appointmentbooksoftware.net - 590
automatedappointmentreminder.com/.net - 390