Thanks Mike,
It turns out the solution was easier than I expected , courtesy of a well directed link from Mike.
The only change in NOF was to name the iFrame, although this wasn't necessary really as I could have used the default name, but I named it "frame_name" anyway.
In AWM I created buttons with links as follows:-
Code:
http://subdomain.domain.com/shop.php?sid=594631&search[text]=heart
http://subdomain.domain.com/shop.php?sid=594631&search[text]=club
http://subdomain.domain.com/shop.php?sid=594631&search[text]=diamond
http://subdomain.domain.com/shop.php?sid=594631&search[text]=spade
and used the "link target" of an iframe with a specified name of "frame_name" to match the NOF page that calls in the iFrame from http://subdomain.domain.com.
I tested the process using simple html before coding AWM, so, for non AWM users, who want to have a page that includes an iFrame but pass a parameter to it you can also use a standard href to achieve the same thing, as per the example I stole from...
<a href="http://www.google.com" target="frame_name">Google.com</a><p>
<iframe src="http://www.yahoo.com" name="frame_name" width="100%" height="90%"></iframe>
If someone needs to do the same and doesn't understand my explanation just shout.