I need a repair manual for a craftsman rear tine tiller. Where can I find one?

Here's a link to a manual for your craftsman rear tine tiller CRAFTSMAN 917 296020 Owner Manual

If you cant move the tines by hand then I wouldn't think you sheared the pins, more like a gear box problem.

Go to sears.com. at top of page about center of page find parts. put in model #. It will give you a breakdown of the whole tiller.
R.G.S.

check to see if there is a snap ring on the shaft or a roll pin.

See if these website folks can help you...
http://community.craftsman.com/Craftsman-14-In-Rear-Tine-Tiller-reviews?tab=details

find your model number from the list on this link and click to get your manual

http://www.managemyhome.com/mmh/owner_manuals/search?query=Craftsman+rear+tine+tiller

there is a manual on e-bay $3.75
I hope this helps

If you find one please let me know as I have the same tiller and no manual.

It sounds like the belt just stretched. Now you need to move the belt tensioner over to put more pressure on it.

Try this website.  http://c.managemyhome.com/mmh/ You will need to register.... and go to home page... manuals.... put in Craftsman and serial number. Pdf should come up, you can download or print.
I worked for me on a mower manual that no one could track down
Hope it works for you

John Elsegood