Here's the code you have for your original image:
<a rel="bookmark" title="Australian Fly Fishing Museum" href="http://www.affm.net.au/wordpress">
<img alt="Australian Fly Fishing Museum" src="http://www.affm.net.au/wordpress/wp-content/uploads/2013/12/AFFM-Mono-invert.png">
</a>This could be simplified to:
<a href="http://www.affm.net.au/wordpress">
<img src="http://www.affm.net.au/wordpress/wp-content/uploads/2013/12/AFFM-Mono-invert.png"></a>So now with your new image, my code in previous post becomes:
<a class="parent" href="http://www.affm.net.au/wordpress"><img src="http://www.affm.net.au/wordpress/wp-content/uploads/2013/12/NewImageName.png"></img></a>
Having added that ahead of the code you added, you should then be able to relocate it using something like:
.parent {float: left;} or more likely:
.parent {position:relative; top: 0px; left: 0px;} and change the 0px to get it positioned where you need.
Phew. If that works, go and get a beer ;)