i haven't found a one piece valencia barangay map but i'd think the municipal hall would have one.

you can get a list of valencia barangays on the valencia wikipedia page.
Valencia, Negros Oriental - Wikipedia

and you can search individual barangays on google maps.
for instance: search Jawa, Valencia, Negros Oriental
Google Maps

you can highlight the roads that google has driven with their street view camera car by dragging the street view icon over the map.

simply amazing, eh...