easiest way to get to prague?

First, define "cost effective" for you.

Try Wizz air, flies from Venice/Treviso ( TSF ) to Prague ( PRG )

It would probably be easiest to fly since a train would take around 13+ hours to get from Venice to Prague. You can find inter-European budget flight schedules and book a ticket on www.skyscanner.com. You can see train schedules for all of Europe at www.bahn.com. Also check out our website for train fare estimate maps, links to purchase tickets and more tips at www.ricksteves.com/rail.

Michael,

As the others have mentioned, travel by train on that route is not the best option as it will be about a 14 hour trip with several changes, so a budget airline would be the most efficient. Some of the budget airlines don't offer flights every day, so you'll need to do a bit of searching to find one that both fits your schedule and your budget. Flights for June 2015 probably won't be listed for a few months.

In the same situation, I'd consider a somewhat "unconventional" route. One option would be to travel from Venice to Milan by train, take the Malpensa Shuttle to MXP Terminal 2 and then use EasyJet to Prague. They currently offer flights every day and the prices will be good if you book well in advance. I had a brief look at their schedules and connecting with the morning flight that departs at 10:20 may be a problem from Venice, so you might be better with the evening flight that departs at 19:55.

Another method would be to split the trip into two days by stopping at an intermediate point for one or two nights. Munich would be a good choice. The trip from Venice to Munich by train will be about 6.5 hours and from Munich to Prague by Bus will be about 4.5 hours.

Good luck with your planning!