Do you have a mobile phone that uses the Windows Mobile operating system?
Are you interested in some new software to make sending those messages simpler?
SMS Déjà Vu might be just what you need then.
It makes it possible to send a predefined message to a person in just two clicks - subject to a mapped hardware button to launch it.. (That's faster than anyone can type!)
At the moment the app is usable but far from perfect.
I'll happily send you a copy if you give me feedback/suggestions while I make changes to get it in a state where it can be widely distributed.
Drop me an email (matt [at] mrlacey [dot] co [dot] uk) if you're interested.