Since the source is docbook xml, XSLT would be a good place to start. You can define transformations to any format you like.

Added:
Since your FAQ probably only changes at intervals, It would improve response to keep static copies of the transformed versions, perhaps with make run from a cron job to handle updates.

The book Perl & XML shows two major approaches to transformations in perl, xslt and callbacks on parsed xml trees, which you suggested on cb you might prefer.

After Compline,
Zaxo