  We provide a library of some 7000 SEDs for starbursts and ultra luminous
galaxies (http://www.eso.org/~rsiebenm/sb_models). Its purpose is to quickly
obtain estimates of the basic parameters, such as luminosity, size and dust or
gas mass and to predict the flux at yet unobserved wavelengths. The procedure
is simple and consists of finding an element in the library that matches the
observations. The objects may be in the local universe or at high z. We
calculate the radiative transfer in spherical symmetry for a stellar cluster
permeated by an interstellar medium with standard (Milky Way) dust properties.
The cluster contains two stellar populations: old bulge stars and OB stars.
Because the latter are young, a certain fraction of them will be embedded in
compact clouds which constitute hot spots that determine the MIR fluxes. We
present SEDs for a broad range of luminosities, sizes and obscurations. We
argue that the assumption of spherical symmetry and the neglect of clumpiness
of the medium are not severe shortcomings for computing the dust emission. The
validity of the approach is demonstrated by matching the SED of the best
studied galaxies, including M82 and Arp220, by library elements; one example is
shown for a galaxy at high redshift (z ~ 3). Generally, one finds an element
which fits the observed SED very well, and the parameters defining the element
are in full accord with what is known about the galaxy from detailed studies.
