Instructions
Research the types of arrowheads that were used by Native Americans in your region. There are many books and websites available to research this subject, including "Arrowheads &Stone Artifacts: A Practical Guide for the Amateur Archaeologist" by C. G. Yeager.
Study your state's historical records to see if there are known river routes that Native Americans would have taken to travel. You might even find information on camp grounds and other areas that were utilized in this manner.
Search after a rain when the layer of dust has been washed off the rocks and new items are uncovered. Also search around river banks and lakes when the water levels are lower and parts of the river bed are exposed.
Look for signs that Native Americans camped and worked in an area. This could be blackened stumps used for fires, pieces of flint that have been deliberately chipped, and other Native American relics. If you find an area that looks likely, use a sieve to pan through the mud and rocks near the creek or river bank to search for pieces.