We introduce a numerical procedure to investigate the spectrum of massive
modes and its contribution for gravity localization on thick branes. After
considering a model with an analytically known Schroedinger potential, we
present the method and discuss its applicability. With this procedure we can
study several models even when the Schroedinger potential is not known
analytically. We discuss both the occurrence of localization of gravity and the
correction to the Newtonian potential given by the massive modes.Comment: 22 pages, 12 figure