What we have for an "owner's manual" is a white 3-ring binder with manuals for the water heater, fridge and other components. If you want to know how to clean the exterior, winterize, etc. click on "files" (upper right corner). There are a lot of PDF files with a lot of information there that Sunline Fan uploaded.
Most repairs and maintenance issues have been covered very well in the "technical forums". If you don't find an answer, ask and someone will be happy to help.
Sunline Fan has a registery with a lot of info on coaches. Check out the "Production Information & Owner's Manuals" forum to submit your vin (or at least the last four #'s) and he may be able to give you some history of your camper.
Welcome to SOC. I'm sure you will enjoy your new to you camper as the rest of us here enjoy ours.