[WTA] - GSM weather transmitter

HI everyone, im in need of help and lots of advice,

i currently doing my final yearproject and i got a random project titled Wireless GSM weather Transmitter. Basically the project will send weather information on demand and also at preset times or when certain criterias are met.

Ive done some reading here and there but none has complete imformation on this.
what i need to know is what are the components needed to make the hardware.
besides the microcontroller, what are the parts i need to purchase to make this happen. Ive read on gsm modules and etc, are there any recommended ones? i need something cheap and easy to implement and needs to hav RS232 interface.

basically what i need is :
GSM module, SIM CARD, MICROCONTROLLER ? am i right?
any help ?

bump? anyone?