adsense and wordpress and positioning

my page is http://www.hiphopmusicnow.com want im trying to add is adsense under the archieve on the left side, i have wordpress, iv searched all through online and i could not find a answer , i have to add the adsense code to editor then click sidebar1.php and i want it to be under achieves soo i know to add it to the bottom, my question is , i want to keep it on the left side when i add the code it goes in the middle wants a html code to keep it on that side, i found 1 but it travels with u along the scroll bar exiting out my bloggin and part of the header, so i just want to keep it on on position and not travel through the scrolling……. help please!