To follow up: I tried again on a freshly updated Debian Testing VM. The problem persists.
1. I started Emacs, C-h i. There was no Emacs manual. 2. I installed emacs-common-non-dfsg after activating the non-free repo. 3. Start Emacs, C-h i, the Emacs manual was now accessible. The Org-mode manual was also present. 4. Install org-mode-doc. 5. Start Emacs, C-h i, the Org Mode Guide was still not available in the Emacs help system. 6. sudo ln -s /usr/share/doc/org-mode-doc/orgguide.info.gz /usr/share/info. FAIL. There is no entry in the Emacs help system for Org Guide 7. sudo install-info/usr/share/info/orgguide.info <http://orgguide.info/>.gz /usr/share/info/dir SUCCESS! The Org Guide is present in Emacs help You probably have to copy the info file to /usr/share/info and call install-info in your debian/rules file, Hope this helps, cheers, Morten