Google "Computer stores in Italy". Filter the results to the last year so the results are more likely to be current.
Look for stores close to where you will be visiting/working. Then google for the stores and any websites that they may have.
Make a list of the components you expect to or may need to purchase. Compare to what the stores sell direct or may be able to order for you.
Look for store reviews as well. Learn what customers have to say about products, pricing, service, and support.