You can't purchase LT2009 anymore. Even to just 'add' a license.
Contact an Autodesk reseller in your region to see if there are any pricing specials/discounts available to you and what options there are, if any.
http://www.autodesk.com/resellers/locate-a-resellerThe Online store is not hard to navigate since you cannot buy an upgrade to LT2009 if you want to purchase direct, just select the AutoCAD LT link, LT2015 is the current for-purchase choice:
http://www.autodesk.com/store