Issue with sidebar widgets not showing when I do custom queries

When you do a query, you change the environment, specifically the current post and query objects. To reset things back to how they were before the query loop you should:

query_posts('post_type=offered'); 
if(have_posts(){
    while (have_posts()) : the_post(); ?>
    ....content
    endwhile;
}
wp_reset_query(); // reset query!!!!

or

$wanted_query = new WP_Query('post_type=wanted');
if($wantedquery->have_posts()){
    while ($wanted_query->have_posts()) : $wanted_query->the_post();
    ....content
    endwhile;
}
wp_reset_postdata();

etc, also, check if you have posts before doing the loop, rather than going straight into the while loop.