Richard Castera

I'm so use to using jQuery that I usually don't have to look up documentation on how to use certain functions. They almost come naturally because it's so English-like! Unfortunately Magento uses Prototype as it's native choice of Javascript Frameworks. I sure wish they would have chosen jQuery! I think they would have more people jumping on their platform. I'm sure they have a good choice for it. Anyway, here's how to check:

if($('id_of_element') != undefined) {
    alert('Object exists.');
}