How can I position an image in terms of x and y?

The image can float over other objects since I've applied a drag/drop script to it, all i need to do is make that image start at a certain position in the page in terms of x and y.
Here is the drag/drop script:
http://www.dynamicdrive.com/dynamicindex11/domdrag/index.htm

Giving the image an ID and then setting its position to absolute would allow you to set top and left values in CSS.