Authors List with Specific Post Count

I am currently using this to print a list of all authors who have 1 or more posts that are published. But my code fails to output the website, facebook, or twitter information. Can anyone help me figure out what is wrong here?

function contributors() {
global $wpdb;

$authors = $wpdb->get_results("SELECT ID, user_nicename from $wpdb->users WHERE display_name <> 'admin' AND ID <> '57' ORDER BY display_name");
$post_count = get_usernumposts($author->ID);

foreach ($authors as $author )

{

	if (get_usernumposts($author->ID) >= 1){

	echo "<li>";

	echo get_avatar($author->ID);

	echo '<div>';
	echo "<a class=\"authname\" href=\"".get_bloginfo('url')."/author/";
	the_author_meta('user_nicename', $author->ID);
	echo "/\">";
	the_author_meta('display_name', $author->ID);
	echo "</a>";
	echo "<br /><div class=\"authdet\">";
	if ((get_the_author_meta('user_url', $author->ID) != '') && (get_the_author_meta('twitter', $author->ID) != '') && (get_the_author_meta('facebook', $author->ID) != ''))
	{
		echo "<a href=\"";
		the_author_meta('user_url', $author->ID);
		echo "\">Website</a>";

		echo " | <a href=\"";
		the_author_meta('twitter', $author->ID);
		echo "\">Twitter</a>";

		echo " | <a href=\"";
		the_author_meta('facebook', $author->ID);
		echo "\">Facebook</a><br />";
	}
	elseif ((get_the_author_meta('user_url', $author->ID) != '') && (get_the_author_meta('twitter', $author->ID) != ''))
	{
		echo "<a href=\"";
		the_author_meta('user_url', $author->ID);
		echo "\">Website</a>";

		echo " | <a href=\"";
		the_author_meta('twitter', $author->ID);
		echo "\">Twitter</a><br />";
	}
	elseif ((get_the_author_meta('user_url', $author->ID) != '') && (get_the_author_meta('facebook', $author->ID) != ''))
	{
		echo "<a href=\"";
		the_author_meta('user_url', $author->ID);
		echo "\">Website</a>";

		echo " | <a href=\"";
		the_author_meta('facebook', $author->ID);
		echo "\">Facebook</a><br />";
	}
	elseif ((get_the_author_meta('twitter', $author->ID) != '') && (get_the_author_meta('facebook', $author->ID) != ''))
	{
		echo "<a href=\"";
		the_author_meta('twitter', $author->ID);
		echo "\">Twitter</a>";

		echo " | <a href=\"";
		the_author_meta('facebook', $author->ID);
		echo "\">Facebook</a><br />";
	}
	else
	{
	}
	echo "<a href=\"".get_bloginfo('url')."/author/";
	the_author_meta('user_nicename', $author->ID);
	echo "/\">";
	the_author_meta('display_name', $author->ID);
	echo "'s Profile";
	echo "</a>";
	echo "</div></div>";
	echo "</li>";
	}
	}
}