This is an old trick, but in case you missed it i am re-publishing it. This is a really simple thing to do. Just follow these steps.
1. Open functions.php in your theme editor.
2. Add this line where you find appropriate:
add_post_type_support( 'page', 'excerpt' ); // Enable excerpts for pages.
3. Save your file.
In a default wordpress theme pages are only listed on search pages. In order to use excerpts, you need to convert the_content calls to the_excerpt in your appropriate template (search.php if exists).