How is this done ?

How do you create the stretched faded out image effect on a site.

Please see http://www.eskerhills.ie/ for example

How is the grey image created on the top of the site that stretches across the whole width of the page

 

I don't see it

 

You need an image (.gif or .jpg is fine) made with your favorite editor this way:
width: 1 pixel (or more)
height: You choose (800 is ok)
Fill that image with a gradient (foreground to background for example).

Use that image on your html. Example (CSS):
body { background: #FFFFFF url(./your_image_800.jpg) repeat-x; }

 

they took this image:
http://www.eskerhills.ie/assets/bkg002.gif

and put it on their body in CSS thus:

body {
background:url(assets/bkg002.gif) top left repeat-x;
}

Which tiles that tiny stripe of an image across the top of the page.