Hi im new to JSON so im not surprised that its been a slight uphill battle but i believe im 1 line of code from being able to put JSON behind me today and i just cant quite crack it

Response: http://www.radiopayback.com/getimage...2010%20Mix%203 Stupidly long (its a google search request for an image),

i only want 1 element:
Code JavaScript:

but i cant seem to get the syntax correct within my script:
Code JavaScript:
var obj = new Object();
var obj = $.getJSON("/getimage.php?path=" + artist + " - " + title);
var cover = new Object();
var cover = obj.responseData.results[0].unescapedUrl

console confirms the obj variable is being passed the JSON information including the "responseText".
error i am getting is "Uncaught TypeError: Cannot read property 'results' of undefined"

any help would be greatly appreciated