Magento how to find if a product is new to add new tag
If you need to add a new tag to a product you need to find out whatever the product is set as new or not.
Here is the method I use:
<?php if (date("Y-m-d") >= substr($_product->getNewsFromDate(), 0, 10) && date("Y-m-d") <= substr($_product->getNewsToDate(), 0, 10)) : ?>
<!-- replace the line below with the stuff you need to display if product is set as new -->
<div class="tag-new"><?php echo $this->__('New'); ?></div>
<?php endif ?>