imageYouWant = new Image;
imageYouWant = new Image();
imageYouWant = new Image(100,300); // with size
the Object then is requested by
imageYouWant.src = "some/image/pathname/on/server.jpg";
you can add an onload event or as I prefer, onerror with a handler to handle errors.
you can also do this as an array of objects
you can iterate through the document body and use the image object to control your image loads.
document.images.length and a loop and the image load... your then cooking in less than 15 lines of code including comments.