British Airways, Finnair, Iberia, American Airlines and various other airlines have round-trip flights from Houston (IAH) to Pisa (PSA) for $672-$689 with one or two connections. Flights October to February. No Weekends. Departures on Monday, Tuesday, Wednesday, and Thursday. 7-day minimum stay required.
Getting to smaller airports like the one in Pisa tend to require multiple stops. This will require one or two to get into and out of, depending on the dates you select.