start researching on google - old schools- parks- cellar holes - old farm fields - old houses
ask permission when needed - anywhere where people were you will find stuff
most of the parks and schools were probably hit years ago - you will always find freshly lost items
research will lead you to the older stuff
ask old timers that have lived in the area their whole life for spots - go to historical societies in area
ask family friends and co workers that have old houses or farms if you can hit there
you can find old maps usually at your local library or on line also
I have been detecting all around my yard and the old rock walls and I found alot of horse buckles and square nails and horseshoes. I really want to find a pine tree shilling