If you are looking for physical "paper" instructional materials specifically for this version, these official guides are still widely available:
: This is the full professional version on a physical DVD. It is listed at Office Depot for $499.99. Corel Coreldraw Home & Student Suite X6 (Boxed Version)
: Pre-owned versions often include the original disc and outside box. You can find these on eBay starting around $63.75. CorelDRAW X6 Educational Books (Paperback)
: A more affordable physical box set licensed for non-commercial use on up to 3 PCs. New copies are available at eBay - lukesten for $179.99 $299.99 . CorelDRAW Graphics Suite X6 Used Box Set