First we need to set up the inventory level of a product at which it will be considered as low stock.

1. Login to admin and navigate to System >> Configuration
2. Scroll down to the Catalog tab and click the Inventory section to open it. Now expand the 'Product Stock Options' section.
3. Set Manage Stock as 'Yes' and add a value for 'Notify for Quantity Below', save the configuration. Note that you do not set 'Notify for Quantity Below' as 0 as it disables the RSS feed.

 <reference name="category.products">
    <action method="setTemplate">
        <template>catalog/category/custom-category.phtml</template>
    </action>
</reference>

These category pages need to show the products in a different layout.

In order to achieve this you may create a CMS static block and add the following segment of code:

{{block type="catalog/product_list" name="product_list" category_id="2" column_count="4" template="catalog/product/list.phtml" }}

This will display the products listing page as a block on the page.