Replace the dvipdfm.def in your LaTex distribution with the one
provided by the latest dvipdfm distribution.  This is necessary for
.eps and .png file support.  The install script will not do this
for you because I do not believe it is healthy to overwrite a file
supplied by a different distribution.

The file dvipdfm.def from the latest dvipdfm distribution may be 
found in /usr/local/share/dvipdfm.  The file that should to be 
replaced may be found in /usr/local/share/texmf/tex/latex/graphics.

Edit the config script in the texmf/dvipdfm directory and change to
suit your needs.  An important configuration option is to set the
helper application for converting PS/EPS files to PDF format.  By
default this is setup for GhostScript.  If the idea
of executing running a command in a shell scares you,
comment out the line with the command string.  Alternatively,
if you really want to disable it, comment the #define HAVE_SYSTEM
in config.h 

IMPORTANT: If you installed this from the packages rather than the
ports, you MUST run mktexlsr as root.