You can build 2 regulators in one unit :
7812 for the 12V @ 1A max...go for a higher current output if you think you are pushing the 1A limit.
78L05 for the 5V @ 100mA max
The problem you may have is the 12V, since you need > 12 to get 12V out on a standard regulator.
But check if your device can take unregulated voltage, if it can and its within the car battery range then you are sorted...no need for anything.