Forum Moderators: open
First, forgive the "official" thing, but url's are not permitted, see TOS.
Anyway, it should be as simple as placing the ad code between the <body> tag and the first subsequent tag, whether it be <table>, <div>, <p> or whatever. This should automatically push the page down and insert the code, but of course, you have to view the site live (generally) to see the results.
Marshall