How do I insert small adds ? [help with adds pls]

Hi , thanks v much to the last answer, he was a good poster.-

anyway – i would like to have very small 20 x 20 px ads on my site – you may have seen them around, like in teh footer of this site – http://circleboxblog.com/

i need a plugin or very simple hack cos im s**t with code, cheers alot ,your always v helpull.