Near Lakes and Rivers
Any large water source is a prime location for finding arrowheads. Rivers and lakes are gathering places for wild game, and therefore likely locations for lost arrowheads and hunting utensils. Take advantage of natural erosion by searching just after a rainstorm. The water washes away the top layers of dirt, exposing arrowheads that were previously buried. Check any hills in the surrounding area, working your way up as you follow the natural path of the rainwater.
Creeks
Find arrowheads and other artifacts in the stream beds of creeks. Sand and gravel bars sometimes contain arrowheads lost centuries ago. Any upper portion of a creek that features rapid washing might hold artifacts recently deposited in the water system. The finer sediment washes past and leaves these items clearly visible. Increase your odds of finding arrowheads by hunting in places where two or more water sources join.
Plowed Fields and Construction Sites
Man-made disturbances in the soil frequently bring up previously buried arrowheads. Freshly plowed fields won't normally yield immediate finds, and can be difficult to navigate on foot; the odds and condition improve after a rain. Construction sites -- while sometimes dangerous -- might produce arrowheads.
A downside to locations such as these is the potential for damage to the artifacts. Farming and construction implements often scar or break the arrowheads, diminishing the likelihood of a pristine find.
Ancient Campsites and Caves
Learn to identify tell-tale signs of Native American presence. Look for any types of burned rocks, bones, stone tools or flakes from flint knapping. These might indicate the presence of an ancient campsite. If you find any clues, scour the area, examining every rock you come across.
If you live in the American Southwest, be on the lookout for caves. The dry conditions inside a cave are an ideal environment for the preservation of artifacts.