Just take 90 west to Rosselle RD North (not sure on spelling of road) and then fallow Rosselle until you see the entrance for Harper College. It is like a couple of miles from when you get off of 90. You will pass over Rt. 62.
Our you could also turn right on Rt.62 and then turn left into harper about 1/2 mile after you just turned.
Hope it helps
