Sorry I have no idea on shop, I'm by Oklahoma City.
If you can follow the drive shaft from deck back you will see a drive unit, on back side it will have pulley and belt, on that belt it will have a tensioner and if you can get ahold of it see if it will move (if you grab belt and push or pull you should see it move) if it isn't moving spray some penetrating oil where arm pulley is attached too frame and keep moving till free. (You might need to unbolt tensioner to get it freed up)
If you don't have manual go to
Walker Manufacturing click on support, on drop box click manuals and look your mower up, it also has dealer locater right under the manuals on the drop box.
Also take a good look at the belts to see if they need replaced.