http://www.northernextremesnowmobili...ided-tours.php
They both rent and have guided tours. Rented from them in the past when we were without our sleds. Twin mountain has nice trails, but can be a bit crowded at times. A lot of the time we go mid-week. Agree with uptakesaukee, local trails can be a bit rough and tight, probably not the best for first time riders.