I wrote a series of blog posts on this a long time ago which you can find here:
http://rbrundritt.wordpress.com/2008/10/25/ve-imagery-service-and-custom-icons/ http://rbrundritt.wordpress.com/2008/11/03/ve-imagery-service-polygons-and-polylines/ http://rbrundritt.wordpress.com/2009/02/22/drawing-routes-with-the-ve-web-service/ http://rbrundritt.wordpress.com/2009/02/14/veimagery-service-pixel-to-latlong-calculations/