Instructions
Log on to the Lego website. Click on "Shop" and you will go to a page that has all the new products shown. Look under "Shop Features" and you will find a subsection titled "Sales and Deals." Here you will find older Legos that are already discontinued or are about to be discontinued.
Visit the Lego Shop website. This website only sells Legos that will be re-released as "Lego Classics" or "Legends." Click on the subheading "Exclusives and Hard to Find" then search for the discontinued Legos you want to find to add to your collection.
Check out the Brick Link website for Lego enthusiasts. The Brick Link group knows the value of Legos and are in the business of trading them.
Shop at the Old Lego website. This website is devoted entirely to vintage Lego collections. Here you can find rare or discontinued Legos from a collector who had duplicate sets.