The next step is to do a bit of snooping. Find out what types of advertisers are on similar sites to yours.
Once you've got that info, work the phones and do some "warm" calling -- contacting the types of companies that fit the above stated equation, whose products or services are within your target markets' interests and geographic footprint.
Don't discount the value of getting your university website in front of prime target markets by doing a bit of online advertising yourself, in carefully researched venues. Use social media, too, and try to connect with another entrepreneur who runs a similar (yet non-competing) business and ask how he or she attracted site advertisers.
Related: Four Ways to Get Advertisers on Your Site