Where is the model number located on a John Deere 68 and what size belt do I need for the blades to work?

Looks like you can open this book for less than $20. I will see if I can get in without paying. John Deere 68 riding mower operators manual (http://www.agriconmanuals.com/john-deere-riding-mower-operators-manual-p-18809.html) Or you can start searching here http://images.google.com/images?hl=en&q=john+deere+belt+diagrams&um=1&ie=UTF-8&ei=fFPlSeyMFZu0MNWQwY0J&sa=X&oi=image_result_group&resnum=1&ct=title