Wait for script to finish before starting function

In a WordPress page I have a WordPress plugin (Showoff) that loads DOM elements onto the page. I want to create a way to link to these DOM elements from outside that page using this code:

var getUrlParameter = function getUrlParameter(sParam) {
    var sPageURL = decodeURIComponent(window.location.search.substring(1)),
        sURLVariables = sPageURL.split('&'),
        sParameterName,
        i;

    for (i = 0; i < sURLVariables.length; i++) {
        sParameterName = sURLVariables[i].split('=');

        if (sParameterName[0] === sParam) {
            return sParameterName[1] === undefined ? true : sParameterName[1];
        }
    }
};

var gotoProduct = function gotoProduct() {
    var productID = getUrlParameter('product');
    var showoffInit = showoff().init;
    if ($(productID).length) {$('.'+productID).click();}
}

but any link will be invalid unless all the DOM elements have been loaded. I tried various methods posted here but none seem to work for me. I think part of the problem might be that the code called by the plugin is called after the DOM is ready only.

So I need to find a way to wait for these DOM elements to finish loading before calling my function.

Any suggestions will be most welcome!