there's plenty of airports around the area. The biggest one is Marco Polo/Venice... but then there's little ones where Ryanair + other small companies fly like German Wings or Wizzair... I know there's an airport in Trieste but never been there... there's also Treviso for sure, which is the one I always fly from/to... then Verona, Bologna... all pretty close... depends from which city you're flying...
Ferrara and Firenze are easily reached by train. And yes, there's special prices (not for tourists, for everybody) if you book in advance... it's an offer called 'mini' and you can find it at the trenitalia site (
www.trenitalia.com)... I've actually bought my train tix to and back from Firenze today, 19E each way with this offer... half price of regular price...