Installation question

Oh wise ones,

Novice trying to install postgresql-7.3.2 on linux.

I am not root, but do have sudo priv.

I unpacked the tarball in /usr.local/pkg/postgresql-7.3.2.
I got as far as adduser which failed.

Can someone point me to the error of my ways?
Implications for subsequent steps?

regards,

Charles

./configure ok
gmake ok
sudo gmake install ok
adduser postgres fail

[chauser(at)gulliver postgresql-7.3.2]$ adduser postgres
bash: adduser: command not found

mkdir /usr/local/pgsql/data
chown postgres /usr/local/pgsql/data
su - postgres
/usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data
/usr/local/pgsql/bin/postmaster -D /usr/local/pgsql/data >logfile 2>&1 &
/usr/local/pgsql/bin/createdb test
/usr/local/pgsql/bin/psql test