Ada-Hi Falls is a well-publicized tourist waterfall with easy access in Black Rock Mountain State Park. Unfortunately, this 40-foot waterfall has a tiny watershed size, being located high in the headwaters of Taylor Creek. I've only seen it with a small stairstepping trickle, much of the waterfall being a mere wet, mossy rock. However, I have found other photos on the internet showing surprisingly impressive flow on Ada-Hi Falls, but one would likely have to visit in very wet weather to catch this waterfall in its prime. The well-maintained 0.2-mile Ada-Hi Falls Trail leads to the waterfall. 

For detailed directions, see page 311 in Mark Ozboyd's "Waterfalls of Georgia" guidebook.