New Babbage is a good starting point for ground vehicles, because there are vehicle pads and hangars near The Commons. Get your Cutty in NBIS, fly the short distance to the city itself following the hyperloop train lines, look for the domes where The Commons are and listen for its music so you know you're near. The landing pads and hangars are in among the domes there. There are vehicle spawn terminals inside the hangars to call your ground vehicle, and go load it into your ship.
Similar with Loreville - I can't remember exactly where the vehicle hangars are there as it's been a while, but I believe they are near one of the city gates. I'm sure Google will tell you.
Area 18 and Orison don't have ground vehicle pads so far as I'm aware. If you're starting from one of those, you'd have to spawn your Cutlass and fly it to a mining station on a nearby moon, where you'd be able to find the Platinum Bay building (blue sign, little vehicle pads next to it) and spawn your ground vehicle there.