To register a 15+ year old vehicle in Vermont, just download the form from VT DMV. Fill it out, get a local (to you) cop to do a VIN verification, and mail the application, bill of sale and VIN verification to the DMV office in Montpelier. In about two weeks they will mail everything back to you along with a temp tag, and a week or so later they will send the actual tag.
You don't have to have it inspected up front, and as long as you never drive it in Vermont you don't even have to worry about getting it inspected. If you do drive it to Vermont, just take it to any inspection station.
You don't have to worry about sending them a title, duplicate or otherwise. They neither require nor issue titles for vehicles over 15 years old. And, should you decide to later transfer the registration to a state that does require a title, that state must by law issue a new title since it will be coming from a non-title state. It has nothing to do with any previous title the vehicle may have previously had, since all previous titles are rendered null and void when you register it in a non-title state.
