Hi guys, I am a bit wary of calling this a tutorial as I am far from an expert (there may be a much easier way of doing it for example!) but it worked for me and maybe someone else will find it useful
How to display the listings in alpha order (instead of most recently posted)
Find the line that says global $wp_query (about line 34)
immediately after it, add:
query_posts( array_merge( $wp_query->query, array( 'order' => 'ASC', 'orderby'=>'title', 'posts_per_page' => 20, ) ) );
Save / re-upload and voila
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