I believe your looking for something like this
<?php
$args = array(
'posts_per_page' => 1,
'post_type' => 'inventory',
'tax_query' => array(
array(
'taxonomy' => 'inventory-category',
'field' => 'slug',
'terms' => array(
'bulk-racks'
)
)
)
);
query_posts( $args ); while ( have_posts() ): the_post();
// do stuff here
?>
<?php endwhile; ?>
Heres how to properly register a post type according to the WordPress Codex page on post types and how to register taxonomies