take a look at this:
http://guff.szub.net/source/page-authors.php
You might need to do a little tweeking with the fields, but its a great start. I managed to use it to get a list of users and emails in 2 seconds. I would show ya the page but there's emails on it, and Im guessing my users would kill me for that :P
That, in its simplest form :
<?php
require('wp-blog-header.php');
?>
<?php
$order = 'user_nicename';
$users = $wpdb->get_results("SELECT * FROM $wpdb->users ORDER BY $order"); // query users
foreach($users as $user) : // start users' profile "loop"
?>
<?php echo $user->user_login; ?>
<?php // echo $user->user_firstname; ?>
<?php // echo $user->user_lastname; ?>
<?php // echo $user->user_nickname; ?>
<?php // echo $user->user_email; ?>
<?php echo " -- "; ?>
<?php echo $user->user_email; ?>
<?php // echo $user->user_url; ?>
<?php echo $user->user_icq; ?>
<?php echo $user->user_aim; ?>
<?php echo $user->user_msn; ?>
<?php echo $user->user_yim; ?>
<?php // echo $user->user_nicename; ?>
<?php echo "<br />"; ?>
<?php
endforeach; // end of the users' profile 'loop'
?>
will grab all users, irrespective of their role.