Your smart to ask for a riding partner, I used to ride alone till one Christmas Eve up in Pittsburg NH about 20 out had engine trouble. Even better no cell coverage up there! Thankfully some riders came along and gave me a ride out after I hiked a good 5 miles or so. I learned my lesson to never do that again.
Secondly, always good to carry a map with you so you know where you are. Don't always depend on there being good or accurate signage out there. The clubs do their best, but a map is a MUST have. NHSA has an interactive one posted here:
http://www.jimapco.com/maproom/snowmobile/nh/ Doesn't have the local trails but at least it helps you get a good look at what is out there in your area.
Finally if you ever want to go for a ride I'd be happy to go out with you, although I'm younger than you I have no desire to ride fast or stupid.