jQuery.preloadImagesInWebPage = function()
{
     for(var ctr = 0; ctr<arguments.length; ctr++)
     {
         jQuery("").attr("src", arguments[ctr]);
     }
}
To use the above method, you can use the following piece of code:
$.preloadImages("image1.gif", "image2.gif", "image3.gif");
To check whether an image has been loaded, you can use the following piece of code:
$('#imageObject').attr('src', 'image1.gif').load(function() {
    alert('The image has been loaded…');
});