My home turf. On the low snow years it's a tough ride. I was always going up through Pittsburg. The best snow hugs the north side of the mountain range. Going through Magantic and staying along the mountains up to St. George the trails mid season are great, but not well marked. The farther north you go, the poorer the snow conditions. I will see if I still have the gps maps. I have not been on those trails in about 5 years. From St. Georges heading north east, there is a great trail that is mostly gas line riding heading up to Cabano.
There are a few club houses, one on the trail coming out from Jackman, another just up the road, just prior to getting up to St. Georges. Keep you sleds chained if you stay near St. Georges. The area usually has some great riding from mid Feb until the end of March. There are a lot of sugaring lines on the trees around St. Albans.
Newport Vermont could be a good starting point. Only sledded over in that area once.