After I ran

dpkg-scanpackages . /dev/null | gzip -9c > Packages.gz
dpkg-scansources . /dev/null | gzip -9c > Sources.gz

in my ~/notebook/emacs/planner directory and added the following entries to `/etc/apt/sources.list’:

deb http://richip.dhs.org/~sachac/notebook/emacs/planner ./
deb-src http://richip.dhs.org/~sachac/notebook/emacs/planner ./

this worked:

apt-get update
apt-get install planner-el