Send text message to cell phone

I am planning a project where the user would click a button in Flash and if registered in database (if not, they would be alerted to register), a short message would be sent to their cell phone.

I understand this can be accomplished by concatenating the users cell phone number with @providersdomain.com see: http://en.wikipedia.org/wiki/List_of_carriers_providing_Email_or_Web_to_SMS

We would need an array of providers addresses to choose the address format from the provider field in the database to be combined with the cell number.

Does anyone know if a script exists for this purpose? How difficult would it be to do this?

Thanks in advance for your help!