I don't need to add too much to the message from Rok; you'll find plenty of accomodations, both country inns and tourist hotels, very tasty cuisine and moderate prices. My favorites are the Catez spa resort, on the road from Zagreb to Ljubljana, the Bohini/Bled lake area in the Alps and of course the gulf of Portoroz on the Adriatic Sea. Many gas stations are open 24h, on main roads and near the borders, and some of them can also exchange currency. I strongly suggest to take a look to Trieste, not only because it's my town but because it's so far from what foreigners usually think Italy should look, taking more of his atmosphere from Vienna than Rome. If you wish to stay here around for one night, can suggest some nice hotel right on the sea. Enjoy your vacation, as June will be a wonderfully quiet month to go around.

Paolo Trieste, Italy