special tags/images display for recent posts only

Hi all,

I’m really new to wordpress and I wanted to duplicate a functionality I had with my previous textpattern set up. Basically I had it set so that new posts , that is posts less than 7 days old, would display a tag which contained an image . So that , all the recently created posts on my page would have a ‘new!’ image icon beside them. And all the older than a week posts would not display this image beside them.

I searched for it but couldn’t find anything. I’m sure I can do this in WordPress, but I wasn’t sure and am no programmer so I wanted to ask to see if anyone could point me in the right direction towards a simple plugin or solution .

thanks so much.