E-Mail Template - Best Practice Please

i am a notes developer & our system currently interprets E-mails from other organisations and auto-creates them as bookings when they are recieved, these Emails are sent from various off the shelf software packages.

i have been asked to design an E-mail template of our own that companies can fill in when they require a booking, send to us and have it auto create.

My question is what is the best method of doing this, what language would be best, has anyone looked into a similar thing before?

ANY ideas please…