Oregon actually has a Stewardship Forester program where you can consult with a Forester for technical information and even support sometimes.
http://www.oregon.gov/ODF/Working/Pages/FindAForester.aspx
Your friend should contact his local Forester for recommendations on how to proceed.
http://www.oregon.gov/ODF/Working/Pages/Replanting.aspx
Replanting information for the different area's of Oregon
http://seedlings.uidaho.com/Store/
The University of Idaho seems to have the best reforestation seedlings catalog, and the Oregon website actually refers to them for ordering seedlings in East Oregon.
For "big" plug trees, $2.50 each, a minimum of usually 5 per tree type, and sometimes a discount when you order more than 200 of the same tree. This size stock includes walnut, serviceberry, wild apple, cherries, etc.
For smaller plug trees, it's $1, a minimum of 20 per tree - and not many varieties, or apparently $0.45 each when you order more than 100. Tho most seem to be out of stock.