Assuming you are talking about a portable MP3 player. Get an FM audio adapter. This is an example below.
http://www.myirock.com/players/irock400fm.asp
You can find these items on-line or at Radio Shack, Best Buy, Circuit City etc.
Do anyone know which companies of MP3 players offer car adapters to their MP3 players? I am looking to buy my first MP3 player, but it has been difficult search to choose which MP3 player I can take with me inside my car. Please help.

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