The LightWave Assets / Plugins database maintains a list of free and commercial third-party plugins available for LightWave.
Batch weld multiple pairs of points
Weld or merge points with options for where they should be placed
Geometry clean-up plugin
Quickly removes the selected layers from an object
Convert the edges of all polygons to 2-point polys
A group of plugins ranging from IK modifiers to UV mapping
Refine a mesh, removing unneeded polygons