Q:

Where can I config service startup options in Ubuntu? 

I'm not used to using Ubuntu or Debian as a server.  I'm more accustomed to Red Hat/Fedora ways and even Gentoo (yikes). 
Under Red Hat installs, you can often configure most services that start from init using config files in /etc/sysconfig named by the service.   Is there and equivalent thing under Ubuntu? 
Specifically I'm trying to control how the libvirtd and kvm processes are started as far as command line options go.  I need to add the --listen option somewhere. 

A:

Ubuntu and Debian use Upstart as a replacement for init, but legacy init scripts are supported.  Chances are that you can add the option in a script in /etc/init.d with the same name as the service.  Also look in /etc/init for .conf files that control the runlevels that services are started and stopped on and how they're respawned, etc.