How can I display a link to a post’s (Word doc or pdf) attachment?

Question

Try this:

<?php

if ( $attachments = get_children( array(
        'post_type' => 'attachment',
        'post_mime_type' => array('application/doc','application/pdf'),
        'numberposts' => 1,
        'post_status' => null,
        'post_parent' => $post->ID
)));
foreach ($attachments as $attachment) {
echo '<a href="' . wp_get_attachment_url( $attachment->ID ) . '">Download Spec  Sheet</a>';
echo '</div>';
}

?>