[jQuery] Append prepend?

[Dave Maharaj :: WidePixels.com]

I cant seem to understand the logic behind these functions. append prepend
appendTo, prependTo
 
I have:
 
<div id="sortable">
 *** add new li from response here ***
<li>content</li>
<li>content</li>
<li>content</li>
</div>
 
so i get my response from the server and trying to get it to appear at the
top of all the other li's and slide down with the hi-lighted effect. All i
get is above the <div id="sortable"> or under the last li.
 
$('#sortable').append(response.html).slideDown('slow').highlightFade({speed:
3000});
      
$(response.html).hide().append('#sortable').slideDown('slow').highlightFade(
{speed:3000});
 
Ideas where i went wrong?
 
Dave