I found this http://www.textssender.com/ but I have problem for installe it, any help with this script or any other idea?
It's not a particularly relevant question as the "script" must be tied up to a service to actually send the SMS's as each API/ Form Handler etc by the service provider will be different. I can provide a link to the PHP script for using it with the organisation we use for SMS sending but its of no use to you unless you want to use the same provider