smsgateway or something like this, help me.

Hello guys, I'm looking for a sms service, if you know or search on google something like paid sms sports betting, there are a lot of blogs with "sms service" a phone number from 4 numbers or something like this, the customers send sms on this number, and they pay some money, and after this I send sms back with the matches for betting, where can I get something like that? Please help me. And sorry if you don't understand what I meaning, but I don't know how to explain.

Anyone know how to make something like this?