The concepts in Tim's Effortless Ctags blog post use Git's init.templatedir setting. Git added the feature in the 1.7.1 release. When I first read the post, my box was running an earlier version. If you're in this boat, the simplest workaround is to putting the hooks into Git's system wide template dir, /usr/share/git-core/templates.
Other alternatives, in case you need them, are either setting the $GIT_TEMPLATE_DIR environment variable or manually specifying the template dir on the command line: git init --template ~/.git_template
(I'll append it here when I get a chance.)