Hello,

it appears that in org-mode 8.x the hooks org-publish-before-export-hook
and org-publish-after-export-hook are no longer used. I did a search in the
source code of org-mode 8.2.1 downloaded from
http://orgmode.org/org-8.2.1.zip, and then looked for one of the hooks
with:

find ./ -name "*.el" -exec grep -H -n "org-publish-before" '{}' \; -print

No entries were found.
Instead, the method for customizing export seems to have been changed to
accept a list of publishing functions in a project-alist:

find ./ -name "*.el" -exec grep -H -n "publishing-function" '{}' \; -print

gives the related code in lines 650-662 of file lisp/ox-publish-el.

If the above is correct, then the org-mode manual should be updated to
reflect the change, at page:
http://orgmode.org/worg/org-configs/org-hooks.html

Cheers,

Iannis Zannos