MichaelH

It is right under Meta on your site (of course if you are logged in already you won’t see that).

Use the taxonomy argument with the template tag, wp_list_categories(), and then click on your particular term to determine the URL.

Also see Template Hierarchy to understand what template will be used in various situations.

Not exactly what you wanted but you can use the $userdata object

<?php
//if user logged in, warn if first name is not filled in
if ( is_user_logged_in() ) {
  echo 'Welcome, registered user!';
  if ( $userdata->first_name ) {
    echo ' You have a first name of '. $userdata->first_name;
  } else {
    echo ' Please, visit your profile page and enter a First Name.';
  }
} else {
echo 'Welcome, visitor!';
};
?>

This uses wp_list_pages to display the grandchildren (level 3) so you need to use the ids from the $gen3 array with your query…

<?php
$gen1 = $wpdb->get_col("SELECT ID FROM $wpdb->posts WHERE $wpdb->posts.post_parent = 0  AND $wpdb->posts.post_type = 'page' AND $wpdb->posts.post_status = 'publish' ORDER BY $wpdb->posts.ID ASC");
$gen1_ids = implode($gen1,', ');
$gen2 = $wpdb->get_col("SELECT ID FROM $wpdb->posts WHERE $wpdb->posts.post_parent IN ($gen1_ids) AND $wpdb->posts.post_type = 'page' AND $wpdb->posts.post_status = 'publish' ORDER BY $wpdb->posts.ID ASC");
$gen2_ids = implode($gen2,', ');
$gen3 = $wpdb->get_col("SELECT ID FROM $wpdb->posts WHERE $wpdb->posts.post_parent IN ($gen2_ids) AND $wpdb->posts.post_type = 'page' AND $wpdb->posts.post_status = 'publish' ORDER BY $wpdb->posts.ID ASC");
$gen3_ids = implode($gen3,', ');
wp_list_pages('include=' . $gen3_ids . '&title_li=<h2>' . __('Level 3 Pages') . '</h2>');
?>

That kind of information is usually displayed using the_tags() and the_category() so figure out what Template is displaying those posts and delete the appropriate code.

Review:
Stepping Into Template Tags
Stepping Into Templates
Template Hierarchy

Use this to list the query_vars:

<?php 

echo "<pre>"; print_r($wp_query->query_vars); echo "</pre>";

?>

If I’ve got it right you need to use http://php.net/manual/en/function.substr.php

Try this:
http://wordpress.org/extend/plugins/custom-post-limits/

Haven’t used this for a while but might see if you can make it fit:

<?php
//for in the loop, display all "content", regardless of post_type,
//that have the same custom taxonomy (e.g. genre) terms as the current post
$backup = $post;  // backup the current object
$found_none = '<h2>No related posts found!</h2>';
$taxonomy = 'genre';//  e.g. post_tag, category, custom taxonomy
$param_type = 'genre'; //  e.g. tag__in, category__in, but genre__in will NOT work
$post_types = get_post_types( array('public' => true), 'names' );
$tax_args=array('orderby' => 'none');
$tags = wp_get_post_terms( $post->ID , $taxonomy, $tax_args);
if ($tags) {
  foreach ($tags as $tag) {
    $args=array(
      "$param_type" => $tag->slug,
      'post__not_in' => array($post->ID),
      'post_type' => $post_types,
      'showposts'=>-1,
      'caller_get_posts'=>1
    );
    $my_query = null;
    $my_query = new WP_Query($args);
    if( $my_query->have_posts() ) {
      while ($my_query->have_posts()) : $my_query->the_post(); ?>
        <h3><a href="<?php the_permalink() ?>" rel="bookmark" title="<?php the_title(); ?>"><?php the_title(); ?></a></h3>
        <?php $found_none = '';
      endwhile;
    }
  }
}
if ($found_none) {
echo $found_none;
}
$post = $backup;  // copy it back
wp_reset_query(); // to use the original query again
?>