IPOD Y Cable

I use the Signal Cable Y cable and it's great. Use it with an iRiver 450 Walkman type player.

kimber
straightwire
http://www.headphone.com/products/cables-and-adaptors/interconnects/straight-wire-musicable-mini-to-rca-1m.php
AP:
http://www.positive-feedback.com/Issue38/analysisplus.htm

Since you're going into a preamp, you should consider a cable that goes from the dock connector of the iPod to your preamp inputs, rather than from the headphone output. That way you're getting a 'line out' signal that hasn't passed through the iPod's internal amplifier.

I don't know if any of the usual high-end cable makers offer one but high-quality versions are available online, like this and this.

I bought a cable from one of those sellers and am very happy with it. The disadvantage of these cables is that you can't run the iPod off external power while it's connected.