newbie in need of help

Okay, your mileage may vary :), however I would approach it with:

  1. find out what interface the load cell requires (i.e. what does it supply - is it an analogue signal or a a digital stream or Serial ....?) this will determine how you connect the load cell to the project.
  2. You will need to probably use the map function to scale accordingly (remember to include some kind of calibration function to set it up right)
  3. Then you can send an email via the GSM shield (have a look at this example and substitute the GSM library classes instead of the ethernet)
  4. So if you can send an email - you can reverse it to revieve and email and parse the text for a key word and the do something....

SO I would start with a MEGA Arduino (the Uno has too little memory to be really useful, a GSM shield and probably a prototype shield so wire the load cell to and to maybe add a buzzer or LED to show someone it is working), You will need an external power supply 12V 2A at least and this should be good to go!