pls advise the most efficient way to get to Pamhagen.. also which is the cheapest option
Travelling from where?
From Surfer's Paradise? ;-)
Bus and train (should) cost the same as the fare depends on how many fare zones you touch.
from vienna airport
Easiest is a bus from the airport to Neusiedl am See then a bus from there to Pamhagen. But depends on your arrival time. Go to http://www.oebb.at entering Flughafen Wien as departure point, Pamhagen as destination and your date and earliest time you think you'll have cleared arrivals by to see the options. Some are long-winded with several changes!