My used C36 didnt come with an owners manual or any other papers that would normally come with a new one. Any ideas on where to obtain them?

You can usually find the owners manual on eBay. The C36, C220, and C280 all share the same manual.
I would recommend callings Mercedes and getting the service history along with original sticker on your car. They can tell you what type of repairs were done to the car by the dealer. Thier customer service department can help you with that and there is no charge for it.