I work just west of the campus and although I havent lived in any apartments near UND I can try to shed some light on ways to search for what you may want. I do know two of the more popular ones just northwest of campus (right off N 42nd Street and 6th Ave N) are Gallery Apartments and Park Place Apartments. For 1 Br or efficiencies rents there I think are right around 500 or maybe just a tad below. I am not sure about the others but there are lots of older apartment buildings in the area from 6th Ave N to Gateway and between University Ave on the west and Columbia on the east.
Most apartments in GF are managed by real estate companies...very few have on-site management...although each complex would have an on-site manager if you will for contact/maintenance info, but for rental info you would have to contact the management company. Here is a list of companies...
Property Management in Grand Forks, ND
Alerus Property Mangement, Goldmark, Elite Property Management are the big ones in town. I suggest calling one of these to get started or do a search for Gallery or Park Place ph numbers.
I also suggest looking at the local newspaper GF Herald as they have a nice site to get all the classified listings in the paper for rentals.
ApartmentsHQ is your headquarters for Red River Valley area apartments
There are a lot of new apartments going up in town...so rentals are much easier to come by then in the past. Since I havent lived in any complex cannot recommend or not recomment any.
I hope this helps start the search.
Dan