I like this one better:
http://gun-deals.com/ammo.php?caliber=9mm+Luger
If you enter your zip, it will calculate shipping to your door-and show the actual cost per round.
(Some retailers -like CTD-charge 3 times as much as others for shipping. That can be pretty pertinent to the overall calculation.)
Gun deals/ammo deals is my 'go to' site in normal times. The problem is now that it's all user entered data, so by the time someone finds a deal, and lets' their 5,000 closest friends know, there's nothing to post anymore.
In normal times this is one of the best sites around though.