You can find the shops here:
Wind - Privati - - Rivenditori
Then refill immediately with at least 10 euros and activate (ask the clerk) the option you NEED. I think the Internet No Stop would be more than enough for 10 days.
At the end you should pay:
- 10€ for the sim-card (including 5€)
- 10€ for the refill (or more, depends on you)
And you should remain with 6€ of credit after the Internet No Stop option is active.
Then you will receive 2 or 3 SMS. The first will tell you that they will activate you the option; the second should be the billing (9 euros for Internet no Stop) and the third the activation. WAIT for this one before connecting to internet. No need to keep the phone turned off (you won't receive any sms if you turn it off...).