Naples is easy to get to by road, air or rail. It has an international airport with flights to most European countries, good rail links with fast trains every hour from Rome and many other Italian cities and a motorway connection to the north, south and east of Italy. Here are the links to help you make your choice of means of transport.
By air: Naples Capodichino airport http://www.portal.gesac.it/portal/page/portal/internet
By rail: The Italian railway system http://www.trenitalia.com
There is a regular bus service from the airport to the centre of the town and there are a lot of taxis in Naples but be careful that the driver has turned on the meter or you can agree to a fixed sum for a trip as established by the local authorities.