Online Aerial Photography
The State of Oregon maintains several web sites that can be used to access Aerial Photography of Oregon.
Oregon Imagery Explorer: An interactive map that allows you to view, compare, and download Oregon imagery (2005, 2009, 2012, 2014, and 2016 NAIP color imagery as well as 2017 OSIP imagery for eastern Oregon)
Oregon Explorer Web Services to Stream Imagery offers the same aerial photography as Imagery Explorer only in a streaming format so that you may use the imagery as background layers in a GIS or other mapping application that accesses data from the Internet.
EarthExplorer is a good place to look for individual aerial photography frames of anywhere in the United States. You can search and download images from a number of USGS aerial photography programs. Elevation data, Landsat data, and other satellite and remote sensing data is also available. Aerial photography in EarthExplorer includes: