Left hand at around 11, while Right hand is on the gearshift knob. (I had paddleshifters on a test drive and in a loaner, I did not like them as much as the real thing).
I have good NPR Music stations in my area (WBJB, WXPN) so I only need to switch stations when traveling from one broadcast area to the next, or to my iPhone for its iPod feature (lurve to MINI for iPhone/iPod integration!).
I often eat breakfast and my pre-workout snack in the car, also. Yogurt is probably the trickiest thing to eat while driving, but juicy pears can also be a challenge.
I often rest my hands on the steering wheel columns at 3 and 9 on long stretches of road… they have the cruise and audio/phone controls on them.