There is a dirt road that goes around three sides of our family estate. Many people have told me that the best time to find arrow heads along that road (and two creeks) is right after a heavy rain. The water washes the dirt off of them and makes them easy to find. Also look where water runs off the road into a ditch. One guy found a beautiful large arrowhead that he sold to a museum for some serious cash.

I wish you success.