Oregon Deadline to...
Oregon is a vote by mail state. However, there are also official ballot drop boxes where you can drop off your ballot. This saves you a stamp, and you don't have to worry about getting it off in time. Ballot drop boxes become available after ballots are mailed out on October 14, and are open until 8pm on Election Day.
There is a ballot drop box on the Eugene campus, outslde the ERB Memorial Union, lower level.
If you would like to know before then, here is a list of Lane County drop box locations, from a previous election which is probably still accurate.
If you are in the greater Portland area:
This should be where you live. If you're a student, you can choose either your campus address or your permanent address as your home, and vote in that location.