Maybe clickatell can point you towards some prewritten scripts. Other than that you might need to hire a freelancer or start learning PHP from the ground up.
Gateways usually receive http posts. cURL is good for that and quite easy to use. PHP email is done with the mail() function. You can look it up in the php.net website. If making an HTML form is beyond your current level of knowledge, then I'd suggest getting a freelancer.
best of luck.
Anti Linux rants are usually the result of a lack of Linux experience, while anti Windows rants are usually a result of a lot of Windows experience.