There are no hostels in Rapolla, but there are other types of accommodations...

An unformal 3 stars hotel, easy to reach and in the city of Rapolla famous for its Spa, which are next to the hotel.
A small village in the heart of Italy, close to the higway and an ideal start to visit many interesting places in the south of Italy, like Alberobello or Matera.
On the highway A16 Napoli Bari, take the exit Candela and follow directions to Rapolla (25 km), than it will be very easy to find the hotel.
Rapolla is a small town.
Via Melfi 170