The LightWave Assets / Plugins database maintains a list of free and commercial third-party plugins available for LightWave.
An interactive version of a Boolean tool
Cage Deformer allows you to freely edit the deformation of your mesh
Interactively conform a foreground mesh to a background mesh
Allows you to distort and animate your object via a lattice
A set of intuitive brush-based modeling tools
You can easily weld and hollow out SubPatch objects without errors