Intsall 8.03 on Redhat ES 3

Is there someone out there that can explain to us mortals how to get
Postgresql 8.0.3 server successfully installed on Red Hat ES 3?  I finally got
7.3.10 to install but no matter what other version I try I get a list of
dependencies, I try to install different rpm to meet the dependencies and they
have dependencies - I have a UNIX background but have been in the window
environment for the last 10 years.  There just has to be a better way to
install programs on Linux.