Pull up to Bull Shoals Boat Dock and you'll find all kinds of help -- and if you want any, probably riders too if you pull up in a SAN 210. The good diving cliffs are on the west shore pretty near the dam. You can't miss, you'll see the other boats. If you ride early and late you probably don't need to know any special cove. By midday, the favorites like three sisters are likely to be over-loved.
If you want more precise info, let me know and give me a couple days (to bring my maps in), and I'll give you some mile markers.