We also use Italsure, here's the link
Italsure - Expatriate Insurance Solutions
But be prepared for higher costs than the UK.
Our Fiesta cost us 200 GBP fully comprehensive when it was UK registered.
It is now 1084 dollars to insure it since we swopped it onto Italian plates.
(Premium is paid in dollars as the policy is underwritten by Clements International and AIG)