If you want to install PostgreSQL 8.0 on FreeBSD via the ports, you probably found this tutorial oder that info.

It seems to me, that some things changed. You better read your shell-output after installation; so you know what todo:

To initialize the database, run
/usr/local/etc/rc.d/010.pgsql.sh initdb

You can then start PostgreSQL by running:
/usr/local/etc/rc.d/010.pgsql.sh start