There are several hotels in the OSU campus area and Airbnb is always an option.
Here is a link to some hotels that are walking distance or a short cab ride away. The best way to get a reasonable price is to check for deals on Booking.com or Expedia or other such sites. A comprehensive list of hotels can also be found here.
The Blackwell Inn (Upscale)
The Mariott (Upscale)
Homewood Suites by Hilton (Midrange)
Redroof Inn (Budget)