The game doesn't provide you with any default setups in the Saved Games Folder, you have to create them yourself by saving a setup in-game. Or you could add some downloaded ones there, but there aren't too many available. We try to encourage the top drivers to post their setups, but they seem to be reluctant to share.
Most of the default setups are pretty good as a starting point, although there are a few cars that are not well setup.
It's best to get used to driving the stages with mainly default setup before fiddling too much into the "black art" (it is a bit like that for me too). I mainly start by adjusting the brake pressures to get the bias better balanced, mainly moving the bias forward, many of the default setups are set to be very loose under brakes and making the rear end let go if you hit the skids too hard.
I also adjust the gear settings to suit the stage.
If you want to understand the "black art" better, the game manual has a good description of each setting.
If you search through this Forum or the main RBR Forum, there are a few good articles, particularly re steering ratios and tuning the steering, I found those helpful.
