Phenomena associated to lasing in random or quasi-random media are of growing interest both from theoretical and experimental points of view. Recent studies show that nematic liquid crystals are good candidates as scattering host for these lasing systems. We present theoretical analysis and Monte Carlo simulations for different modellizations of scattering in nematics coupled with a two-level system which describes the dye action. We also show that a simple description of light diffusion in nematics is inadequate to describe the localization process that is at the basis of the laser action; therefore, different physical phenomena have to be taken into account.