The LightWave Assets / Plugins database maintains a list of free and commercial third-party plugins available for LightWave.
Colorida is a free non-destructive interactive cloning plugin.
Clone Items and their hierarchies
Create "clones" along an object's motion path
Clone an object in layout onto the polys of another object
Many clones of one object on surface of another
Clones the BG object and places them on each selected FG polys