Good luck... you're starting a little bit too late in this game. Since Good Sam is quite close to OSU and fall term starts pretty soon at OSU and all the good spots are already taken by students.
This part of the year, you'd have to call all over to look for a vacancy... and from there, you'd have to eliminate obviously ghetto apartments.
Substantial number of apartments are managed by two companies. One is Pinion, the other is Sterling. Another big game player is Bowman.
I've never rented from Pinion, but I would not recommend it.
Corvallis Gazette Times: Archived Articles
From my limited experience, you get an idea Pinion does as little as possible from day one. When you go look for rental properties, you actually go to their office, you give them your ID and they lend you the key to the vacant unit to go look at own your own.
I looked at a few and they were all in OMGWTFBBQ conditions therefore... i didn't end up renting from them.