[jQuery] How to go about writing a plugin that extends a core plugin like sortable

[jQuery] How to go about writing a plugin that extends a core plugin like sortable

Hi
I would like to turn my code for <a href="http://www.2dnn.com/DragnDrop.aspx">http://www.2dnn.com/DragnDrop.aspx</a> into a plugin. Right now its just standard coding and .sortable.
So lets say i would like my plugin to have the name of igoogle and extend sortable
Is there a good example somewhere or can someone paste some code here so I can go from there
thanks in advance
Armand