Correct answers
Stop by an electronics department of some place like Hastings, Walmart, Radio Shack, bbuy etc. and pickl up an FM Transmitter. It will plug into your car's "cigarette lighter" port, and have a jack that plugs into the headphone jack of the Droid. You set the transmitter's frequency to a "clear" FM channel and tune your FM radio to that frequency, and can listen to your music in stereo.
I picked up one from Hastings Book/music for $25 that also had a USB charging port on it, so I can both charge my phone and use the FM transmitter a year or two ago. Works great.
Of course, some cars actually have an "audio-in" jack these days, but I assume you don't have one, since you asked 
Stop by an electronics department of some place like Hastings, Walmart, Radio Shack, bbuy etc. and pickl up an FM Transmitter. It will plug into your car's "cigarette lighter" port, and have a jack that plugs into the headphone jack of the Droid. You set the transmitter's frequency to a "clear" FM channel and tune your FM radio to that frequency, and can listen to your music in stereo.
I picked up one from Hastings Book/music for $25 that also had a USB charging port on it, so I can both charge my phone and use the FM transmitter a year or two ago. Works great.
Of course, some cars actually have an "audio-in" jack these days, but I assume you don't have one, since you asked