PHP code for logo is in index.php of template:
<div id="logo"><a href="index.php"><img src="/images/logo.png" width="228" height="126" alt="joomla furniture store" /></a></div>
but you don’t need to change that if you don’t want to alter logo size(… width=”228″ height=”126″…).
Simply change image which is one of this:
templates/hot_furniturestore/images/logo1.png
templates/hot_furniturestore/images/logo2.png
...
templates/hot_furniturestore/images/logo5.png