My wife and I just got brand new Mountain Bikes and obviously they both have knobby tires. We all know knobby tires are not great for the street, and will wear down quickly with street use. They're also not the easiest to pedal along with on asphalt.

Where can we find reasonably priced wheels (under $100 per set) for our bikes? I've been "out of the loop" for 22 years, and I've never owned a 26in. bike, so I don't know any of this stuff.