[CentOS] RPM for postgresql 8-* for CentOS4?

> Then I did a whereis/which after running updatedb, and was expecting to
> find pgsql in /usr/local/ or elsewhere, but nothing.

Distribution related packages don't go in /usr/local. That's generally
for people building software from source. Distribution related
packages live mostly in /usr. As Johnny pointed out, rpm -ql
<packagename> will show you what files are in that rpm. Keep in mind
that some names may not be exactly has you expect them.

--
Any sufficiently advanced technology is indistinguishable from magic.
-Arthur C. Clarke