SMS Callback Service
 

Does anyone can advise of a reliable provider that offer good rates and sms call back to make calls?:)

Not just off the top of my head. I will say that many of us have had good luck dealing with CallbackWorld.com in the past. A few years ago I worked out a way to trigger their callbacks by just accessing (touching) a URL. It required data service to work but it used so little data I never saw a charge for doing it. CallbackWorld does offer callback service from a variety of carriers and I think some of them have SMS triggering.

www.sparruf.de

A very interresting service, they offer a lot more!