Adding a "promotional materials" page after the index

Hi all -

I'm trying to add a promotional page after the index - you know, "buy
this other book too, and the t-shirt" and all that sort of thing.  It
would appear after the index, but it's not a back cover, it's just
another page.  I've been poking around for a bit with no luck... any
pointers on doing this?

Thanks,

Tom