Hi,
In the head of your page
<style type="text/css">
a img{
border: 1px solid black;
}
</style>
and then
<a href="page.htm"><img border="0" src="picture.gif"></a>
This will apply to all images that are links, you could add
img{
border:1px solid red;
}
to make all images that arent links have a red border, in both cases changing colour/style/width to suit.
Jon