Eheh, I wish you my best luck!
It's absurd that at the main train station in the capital of Italy they don't speak English, but so it is... BTW go to the first Tabacchi shop you find and ask for a TIM refill of the amount you prefer, give them your number, pay and you will be refilled. Then send the SMS for the Internet Senza Limiti activation. There could be compatibility problems with theTIMxSmartphone, but I hope not...