Step 1: select any microcontroller
select any microcontrollerm like, 8051, Arduino & AVR etc. my sugestion is, select any MC which was you already familiar. if your are new to micrcontrollers, better to choose Arduino
Step 2: connect GSM,GPS,RFID modules to microcontroller.
you can find valuable information in our EG website regarding interfacing of these modules to microcontroller. please go through below links.
http://www.engineersgarage.com/embedded/avr-microcontroller-projects/gps-interface-circuit
Step 3: Write microcontroller code.
add all respective libraries, draw your project function (working) as algorithm, as pe algorithm write code.
if need any help in programming, please post few important details after selectng micrcocontroller. like
which microcontroller you choosen
and your algorithm