United, Air Canada, Delta, Air France, and Lufthansa have round-trip flights from Houston (IAH) to Milan, Naples, or Venice (MXP, NAP, VCE) for $523-$563 with a connection. Flights October to January. No Weekends. Departures on Monday, Tuesday, Wednesday, and Thursday. 7-day minimum stay required.
Some of the cheapest fares have a long connection on the outbound leg of the trip. Most of the good routing is about +$15 more than the cheapest fare.