I think you might find ttmkfdir useful. It's like mkfontdir for truetype fonts. I have used an older version, and I don't know how well it's being maintained. It's now available at http://freshmeat.net/redir/ttmkfdir/10789/url_tgz/ttmkfdir.tar.gz .
I believe ttmkfdir comes with freetype2, now.
--Ray
