Trying to plan car-free travel routes in the US is a huge pain in the butt. If Google maps can't spit out a solution that gets you all the way to your destination, it won't tell you a partial answer.
This means piecing together information from multiple sources. I spent a lot of time checking Amtrak routes and then looking for commuter bus routes, local shuttle services and the like to find a viable route.
In the past few days, I've done some googling to try to see if there is a website that handily aggregates commuter bus route info. There doesn't seem to be such.
In Southern California, you can travel from San Diego to Victorville via commuter bus, but there is no travel site that will tell you that. You have to research all the connections yourself.
(Well, I had to. I posted it to my homeless site: https://sandiegohomelesssurvivalguide.blogspot.com/2015/05/o...)
I have to wonder how many other places in the US actually have similar situations where you can get there via bus or other transit, assuming you can dig up the information.
Living without a car is an environmentally-friendly choice and it's hugely painful in the US, often very unnecessarily so. Serving this need could promote not only environmental goals but also serve social justice because car-free Americans are frequently poor. We make it so painful to live without a car in the US that most Americans who can afford a car have one, even if they don't really want one, with the exception of a few dense metro areas with good local transit (like New York).