The weak attack rating makes them useless as a primary weapon, however, this same characteristic makes them ideal to train with, and these are frequently used by paladins to train their distance skill.
Experiments show that, on average, 3 out of a 100 small stones will break when used. These have the identical range of throwing stars. After update 8.5 the drop rate of small stones by goblins was lowered and prices became higher.
The easiest way of getting small stones is by hunting apes. Sibangs drop them quite frequently. Earth Elemental also drop nice amounts, but are considerably stronger to defeat.