The best collections of published biographies in Oregon are at the Oregon Historical Society Library and the Oregon State University. The Family History Library also has an excellent collection. Some representative biographical encyclopedias are:
Gaston, Joseph. The Centennial History of Oregon, 1811-1912, 4 vols. Chicago, Illinois: S.J. Clarke Publishing Co., 1912. FHL Collection book 979.5 H2g; film 1000359]. Volumes 2 and 3 are biographical.
Carey, Charles Henry. History of Oregon. 3 vols. Chicago, Illinois: Pioneer History Publishing Co., 1922. FHL Collection book 979.5 H2cc; fiche 6046590. Volumes 2 and 3 are biographical.
Lockley, Fred. History of the Columbia River Valley from The Dalles to the Sea. 3 vols. Chicago, Illinois: S.J. Clarke Publishing Co., 1928. FHL Collection book 979 H2Lf; film 1000362 items 2-4.) Volumes 2 and 3 are biographical.
Portrait and Biographical Record of the Willamette Valley, Oregon. Chicago, Illinois: Chapman Publishing Co., 1903. (Family History Library book FHL Collection book 979.53 D3p; film 1000365.
All of these volumes and 43 additional collected biographies are indexed in Patricia Brandt and Nancy Guilford, Oregon Biography Index Corvallis, Oregon: Oregon State University, 1976; FHL Collection book 979.5 D3b index; film 1321470 item 18.