It's located at /etc/httpd/conf/httpd.conf. Once you find what you need, make your changes, run /etc/e-smith/events/actions/restart-httpd-full, then test, if it breaks something, then re-expand the httpd.conf templates, restart httpd again, and your back to where you started.
Once you find what you need, then make a custom template so your changes will survive when updates are applied to your server.
Good Luck,
John Bennett