Add a Menu in the Dashboard

Hello guys,

I’d like to set up a new Page under Presentation, where the user writes a ‘welcome message’ for his blog, pretty much as the blog’s description does, but in a page of its own.

Reading the Codex, I came up with this bit of code, a kind of foundation for that purpose :

<?php
add_action('admin_menu', 'my_plugin_menu');

function my_plugin_menu() {
  add_options_page('My Plugin Options', 'My Plugin', 8, __FILE__, 'my_plugin_options');
}

function my_plugin_options() {
  echo '<div class="wrap">';
  echo 'Here is where the form would go if I actually had options.
';
  echo '</div>';
}
?>

From there on, I’m pretty lost on how to manage all that PHP, what to add, etc.

If the final result must be a simple box, to fill with some text, then output it in index.php … can anybody tell me what to do ?

I know I could use the text widget but I prefer to keep it separated.

Thanks very much indeed,