I couldn't find an owners manual for my rig either. But it was a lot easier to find owners manuals for its major components such as the refrigerator, heater, air conditioner, power converter, stove/oven, propane leak detector and water heater. For some of these, I've also found the larger company books for service technicians - very handy.
The "PDX RV LLC" site has a lot of manuals in their Technical Support Resources section of the site. Simply find the model number on whatever device that you need a manual for and start searching. All in PDF form, of course.
Rick
