I had never seen an indigo bunting until a few years ago and now I see them everywhere! The males are usually high up in a tree- the very tippy top and singing what sounds like to me: "sweet sweet chew chew sweet" or some variation there of. If you hear that look up. Unfortunately they look rather black against the sky. If they are lower down they will make a sharp "spit spit" sound. There are plenty along the road where I live so if you want to take a country drive/walk here are the directions:
From Mount Albert (town is located east of hwy.48, north and east of Newmarket) take Mount Albert side road east to the third concession (approx. 6km). Mount Albert side rd. turns into Ashworth rd. here. You can park along the Ashworth and walk it from the third to the 4th. There is quite alot of wetland here and there are almost always some buntings to be seen in here. There are also some buntings north along the 3rd from the Ashworth. I often see the males down low and they really are spectacular. Aslo to be found in the area are northern waterthrushes, white throated sparrows, vireos, wrens, phobe- often hunting around the bridge, wood thrush, common yellow throats, swamp sparrows and many others I am sure. It is quite a good spot!
Hope you see your bunting!
Brenda