I think I have finally identified one of the birds that for me, marks the arrival of fall by the arrival of their song around the property.  I believe my 'fall song' bird is the Golden-crowned Sparrow (Zonotrichia atricapilla). A very close approximation of what we hear each fall can be found here.

The other two birds that mark the arrival of fall for me are the Northern Flicker (previous post) and the American Kestrel (Falco sparverius). I saw my first Kestrel yesterday afternoon on the power lines at the corner of Stony Point and Jewett.