Hi Annie. no the free listing element doesn't make any difference.
I've got something listed for UK only at the moment, when I go to Revise your Item, go down to the postage section. You will see it says, Domestic postage. Under that should be another box with a drop-down saying "No international postage". Click on that and the second option there is "Flat rate for all international buyers". Click that and then a little raft of boxes should activate - as nibble says, for you to choose worldwide or select which countries (I usually do a worldwide rate and a Europe rate, between them they cover everything).
I realise that it's too late to do it for your listing now ended, but if it didn't sell and you want to relist it so you can contact your Dutch would-be buyer, you can change the postal options at the time you relist, by using the revise or edit options. You could still have sold to the Dutch person btw, by telling them how much p&p would be (using nibble's postage table for example), then letting them bid then correcting the postage when you raised the PayPal invoice to them - it's done automatically if it's on the listing, but you'd have to do it manually otherwise.
I do hope this helps - please come back if it doesn't! It works for me, I had something the other day which was UK only but sold in the end to a foreign buyer.