I too know nothing about books to recommend, I'm studying Computer Engineering (Comp Sci and EE mix, but with more emphasis on EE).
One thing to note:
Volts * Amps = Watts
For the house switch:
120v * 2 amps (guess) = 240 watts (rating of the switch)
Automotive:
12v * 15 amps (driving lights?) = 180 watts (needed rating for the switch)
I personally don't feel like there would be any problems powering some driving lights with these switches, and if it's a relay, even less, since relays don't take very much power to operate.
Mario