Is there a way to have Debootstrap automatically configure locales?

I like to use Debootstrap for making sparse systems (usually a base for something embedded) or paravirtualized Xen guests.

I'm familiar with how to tell Debootstrap what packages I want beyond the typical minimal base, but I have yet to find the right combination of tools to let me specify and auto generate locales after the base system has been installed.

Do I need to do this in my own scripts, or is there a way to tell Debootstrap what locales I want and have it just generate them?

I would suggest using grml-debootstrap. This is a wrapper script around debootstrap and comes from the grml live cd. This script has a file /etc/debootstrap/locale.gen where you can put your locales and they are generated at the right time. grml-debootstrap also has lots of more advantages and its worth to look at.