I just bought the Garmin 60CSX. It's very easy to use,awesome battery life and right in your price range.
You can even download the Wisconsin,Michigansnowmobile/ATV trails and overlap them right on your maps (if you're into those activities). Mine mounts right on the ATV, totally waterproof.
Where I ride in the U.P., I would be lost in the first hour, I highly recommend it!
(Check Ebay, for whatever you get)