Hi there
Here are some projects on EG which deal with GSM and various microcontrollers, check them out:
1. "engineersgarage.com/microcontroller/8051projects/gsm-interface-8051-microcontroller-circuit-code"
2. "engineersgarage.com/contribution/gsm-based-ac-appliance-control"
3. "engineersgarage.com/contribution/gps-and-gsm-based-vehicle-tracking-system"
4. "engineersgarage.com/embedded/pic-microcontroller-projects/interface-gsm-module-call-message-circuit"
5. "engineersgarage.com/embedded/arduino/how-send-message-gsm-module-using-arduino"