"Sled" is kind of a 'city-slicker' way of saying sno-go/snowmachine. The machine is just the power that replaces the dogs; the sled is the 'workhorse' which does the hardwork of hauling stuff. (I've seen elders scold young bucks and send them home when they've seen them out 'in the country' without a sled. Without a sled, they're probably up to no good and might just waste something.)
I live in wasilla so I guess I'm a city slicker...