I have been snowmobiling for a number of years. This is a very fun sport that can be done by all. There are a number of things that one should do to ensure that you are safe and can enjoy the outdoors on your snowmobile.
Snow-friendly clothing is recommended for snowmobiling such as: bibs, jackets, gloves, boots and helmets. Snowmobile dealers offer a full line of clothing that is specifically designed and made to keep you warm. There are also some good websites for clothing.
Carry your cell phone. In some areas reception may not be good but better safe than sorry. Two way radios can come in handy. I had one guy go off the road and we were able to find him by getting him on the radio. Cell phones would not work for this. Most snowmobile's have a little pouch on the back of the seat. I would carry a solar blanket, water, snacks, lighter, and some other things. Tell someone where you are going even if you are in a group. If plans change, call the person and let them know. Carry maps of the area. In a group it is important to stop once in awhile to make sure everyone is accounted for and doing okay.
Check to see if you need to purchase a sticker for using the trails. I know coming from Minnesota if you are in Wisconsin you need what is called a "green sticker". If you don't have one you can be cited and even told that you cannot access the trails. Snowmobiles must be registered in the state you reside in. You can check with you Motor Vehicle department for the particulars.
If you have never been on a snowmobile try it with a family member or a friend.
If purchasing a snowmobile go to an authorized dealer in your area. Beginners will need something with less horsepower . Some models can seat two people. There are many out there so check it out.
Check out the weather. Weather.com or another good site is intellicast.com before heading out.
There are many great places to snowmobile. so go out and have yourself some fun and mabey pick up a new hobbie.