There are 2 steps for that.
First you need to prepare PHP for USD. You can do that at the top of your page anywhere.
<?php setlocale(LC_MONETARY, 'en_US'); ?>
Lastly, you'll want to format your display price as follows...
<?php echo money_format('%(#6n', $row_Recordset['Price']); ?>
I think that should provide you with the output you're looking for..