Robotics, cars,...

I need help. I have an idea to make automatic gear changing, servo
(eletronic) wheels rotating and some more stuff into my car.
Now, I have lots of years experience with programming, computers, physics,
mathematics. But I never tried to combine them in robotics area which is the
most interesting one.

So, could you tell my how to achieve what I want... your opinions, links,
articles, anything that can help. i know that there is lot of work and
learning to do, but i'm willing to do it.
From where to start, what should i get and so on...

thanks