what if you want to hide price for not logged in user or you wanna show product price to only those users who have an account on your store ? If you wanna apply this on your store then you have to update your price.phtml file by using a small code to hide price for guest user.

lets do this :

Open app/design/frontend/base/default/template/catalog/product/ folder and copy price.phtmlfile to the app/design/frontend/theme_package/your_theme/template/catalog/product/ folder and then Place the following code on top of it:

<?php
if(!Mage::getSingleton('customer/session')->isLoggedIn()){
echo '<span class="login_for_price"><strong>Login to See Price</strong></span><br>';
return;
}
?>