Here's an Australian Aboriginal example acquired in the '70s (along with a shield, a woomera, and a penalty spear) from an antique store in Melbourne. The club measures about 27 1/2 inches in length.
The carving is limited to a diagonal cross-hatched pattern on the grip-end that seems more functional than decorative, and two sets of carved rings (visible in the second photo). There is a pitch covering of some sort covering the grip-end that reminds me of the tar pitch used to seal an Apache water tus.
Not nearly as visually appealing as the stunning examples shown in this thread - by comparison, a veritable "ugly stick."