installing packages with dpkg as not-root

[Number Six <40311.nospam@comcast.net>]

Over on debian-devel,
[http://lists.debian.org/debian-devel/2004/debian-devel-200403/msg00624.html],
a thread got started about running "dpkg --force-not-root --root=`pwd`.

I asked the diff. between that and just extracting it, and was told it 
would "update *a* (not *the*) package database).

So I created a new, fresh user, logged in as him, and ran:

$dpkg --root=`pwd` --force-not-root -i /path/to/tar_*.deb
dpkg: unable to access dpkg status area: No such file or directory

I do not know what I should do to have provided the "intitial structure" 
to have made this work.  Please don't just answer "use a chroot" :: 
please give me something like "untar basexxx.deb from the Woody CD".

I'm stuck.