  We use a sample of galaxies from the Two Micron All Sky Survey (2MASS)
Extended Source Catalog to refine a matched filter method of finding galaxy
clusters that takes into account each galaxy's position, magnitude, and
redshift if available. The matched filter postulates a radial density profile,
luminosity function, and line-of-sight velocity distribution for cluster
galaxies. We use this method to search for clusters in the galaxy catalog,
which is complete to an extinction-corrected K-band magnitude of 13.25 and has
spectroscopic redshifts for roughly 40% of the galaxies, including nearly all
brighter than K = 11.25. We then use a stacking analysis to determine the
average luminosity function, radial distribution, and velocity distribution of
cluster galaxies in several richness classes, and use the results to update the
parameters of the matched filter before repeating the cluster search. We also
investigate the correlations between a cluster's richness and its velocity
dispersion and core radius, using these relations to refine priors that are
applied during the cluster search process. After the second cluster search
iteration, we repeat the stacking analysis. We find a cluster galaxy luminosity
function that fits a Schechter form, with parameters M_K* - 5 log h =
-23.64\pm0.04 and \alpha = -1.07\pm0.03. We can achieve a slightly better fit
to our luminosity function by adding a Gaussian component on the bright end to
represent the brightest cluster galaxy (BCG) population. The radial number
density profile of galaxies closely matches a projected Navarro-Frenk-White
(NFW) profile at intermediate radii, with deviations at small radii due to
well-known cluster centering issues and outside the virial radius due to
correlated structure. The velocity distributions are Gaussian in shape, with
velocity dispersions that correlate strongly with richness.
