Depends. If your stereo has RCA inputs, then all you need is a 1/8" stereo plug to dual RCA plugs (red and white) "Y" adapter. Should be able to find one at Radio Shack for about $5.
If your stereo has a 1/8" or 1/4" input, then all you need is an 1/8" to 1/8" extension cable, or 1/8" to 1/4" adapter.
If your stereo has standard stereo wire connectors (the clamp style, or screw style), you'll need to look around and see if anyone makes an adapter for what you're wanting. Either an 1/8" plug to basically bare wires, or something along those lines.
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