The founding fathers thought a lot of things. Some people confuse "what the founding fathers thought or believed" with "what the founding fathers saw fit to codify in the constitution" - big difference. This is why I facepalm every time some yokel starts quoting the Jefferson or Federalist Papers like they're apendix A to the bill of rights. So, if Jefferson was in the libertarian camp, good for him. The document he signed and subsequently swore to uphold had built in mechanisms which allowed it to evolve and grow over time as the needs and interests of the people changed. That was the true genius of the Founding Fathers, not that all the generations that came after them would be held rigidly in obeyance of the Founder's personal philosophies in general.
As for your party, I've read their platform and watched it evolve over the years. Suffice it to say that it's definitely written to have mainstream likeability, but if you drill down into some of the Libertarians' core beliefs, that's where they start to part from reality. Driver's licence? FAA or FCC regulations? Public roads? Compulsory public education? Who needs any of that nonsense? This country would be a very different place without these basic things that Libertarians object to, and I think you'll have a hard time making a case that we'd all be better off in that kind of place.
Don't get me started on Ayn Rand. Her drivel may be understandable in the context of rebutting the Red Threat in the mid-20th century, but the concept of benevolent capitalism unchecked by government has proven demonstrably false time and time again in the last 200 years. Industrial revolution's exploitation of the labor class, Robber Barons, monopolies, rampant industrial pollution in the 60s and 70s. This is what you get with laissez faire capitalism. Hey, let's deregulate the mortgage industry! That worked out swimmingly. Not quite the libertarian utopia we're being sold on the party website.
The primacy of individual rights sounds great on paper until one comes to the shocking revelation that those individuals come together to interact in a society with common goals and needs. We have an active foreign policy and dole out foreign aid because we, collectively as Americans, have interests out there in the world. Isolationism, another central tenet of Libertarianism, has failed every time we've tried it. We can't be naive enough to think that we can live in a bubble while the rest of the world carries on as it chooses. The fact that we haven't fought a war on our homeland in ~150 years is precisely because we have an active foreign policy. All the same principles apply to economic matters, having a central bank and managing our fiscal and monetary policies.
I understand there's a lot of criticism for what Libertarians see as extra-constitutional programs, but just because the execution of our foreign policy and foreign aide programs aren't perfect, doesn't mean they're fundamentally flawed concepts which should be abandoned by the government.
Brett