Does your car have an aux input? If it does, then all you need is a cable. A 3.5 mm with 2 male ends - one goes into the headphone port of the player, the other goes into the aux input port.
If not, does your car have a cassette player? Then you can use a cassette adapter. It looks like a cassette tape with a cable sticking out of it with a male end. That end goes, again, into the headphone port of the player. The cassette goes into the deck.
Have neither? You could use an fm transmitter. However, these are hit or miss. It depends on where you're driving and how crowded the fm stations are. You connect the fm transmitter to the headphone port of the player. You set the transmitter to an open frequency and then you set your car's radio to that frequency.
Your last two options:
1. Get a new head unit with aux input or get an aux input installed. Some car radios allow the latter using the connection that would have gone to a disk changer. I believe it may involve pulling the radio out.
2. You've already mentioned accessory speakers. Since you're going on a road trip, this is not really a good option. You'll probably want something small. And because of that, it's not going to get loud enough unless it is really quiet inside the car. But if you do decide you want to try this route, pretty much any accessory speaker will work. Even the ones for iPods, provided they have an aux input port. And make sure it comes with the necessary 3.5 mm cable or buy one.
I purchased my Samsung T10 in order to listen to recorded books. This it does perfectly. Now my husband and I are planning a driving trip. My question is: Is there any way a passenger and driver can both hear the audio? Are there accessory speakers, connections, or anything like that?
Thanks.

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