Have a look at http://automattic.com/code/widgets/
I use it to specify the sidebar options that stay the same for all sites of my blog. After the dynamic sidebar, I just put my own code (for example related posts), which only appears depending on the kind of page that you are on.
Have a look if it works for you…
To add the sidebar to your posts, you need to edit single.php.
Add <?php get_sidebar(); ?>
just before
<?php get_footer(); ?>
And change “widecolumn” to “narrowcolumn”.
Just did that this morning with one of my sites.
ok, sorry, in that case I didn’t get the question…