Hi Linda,

OSU Extension unfortunately doesn't have a resource collection on sustainable greenhouse construction for western Oregon. 

There is a ton of information on the internet from other institutions and from private sources. To get started try looking up key words like 'passive solar greenhouse' or 'permaculture greenhouse'. There are many options and some will work better in certain climates than others. Specifics to keep in mind for greenhouse growing in western Oregon are thinking about winter heating and year-round cooling. You still may need to add supplemental heat for the coldest nights (depending on the hardiness of the plants you are growing). And definitely need a way to vent excess heat year-round! The amount of sunlight is a major limiting factor for year-round production of many veggies and herbs. So carefully selecting which crops and varieties you grow will be key to success.

Another resource to glean ideas from is the Deep Winter Greenhouses page from the University of Minnesota. Their winters are much much different from ours, of course, but some the key concepts in greenhouse design might be of interest. 

You may also find that the microclimate you are growing in only requires season extension techniques like row covers to protect from winter rain and provide enough cold protection to grow many cool season veggie crops.

I hope this gives you some places to start and best of luck with your growing endeavors!