right align an image using CSS HTML
img {
display: block;
margin-left: auto;
}
<img style="float: right;" alt="" src="http://example.com/image.png" />
<div style="clear: right">
...text...
</div>
jsFiddle.
Float the image right, which will at first cause your text to wrap around it.
Then whatever the very next element is, set it to { clear: right; } and everything will stop wrapping around the image.
There are a few different ways to do this but following is a quick sample of one way.
<img src="yourimage.jpg" style="float:right" /><div style="clear:both">Your text here.</div>
I used inline styles for this sample but you can easily place these in a stylesheet and reference the class or id.