There's a few ways to do this.
1. If you have a cassette deck available in the car buy a cassette adapter.
2. You can buy RCA cables and hook the Zune in through AUX port on the back of your stereo.
3. You can buy the FM transmitter and play it through the radio.
That's the top 3 ways. There are others as well if you look around the net :)
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