To register a new snowmobile, you must download and print an application, then mail it to the DNR, along with the fee and necessary documents, within 15 days of the purchase. You can renew the registration by mail, over the phone (1-866-867-3542), or online. Out-of-state visitors must either register their snowmobile in Illinois or purchase a trail use sticker from a license vendor.
Check out these Normal, IL ATV/OHV resources: