You have 3 options.
1. Wadia with an external dac--perhaps the best route--very impressive but depends on your dac--though can be used in analog mode
2. Red Wine Audio iMod -- see 6moons review -- only for generation 4 and 5 iPods
3. basic analogue iPod dock by Apple (best of the type), Belkin, Kensington etc
I've heard all 3 and definitely prefer the Wadia.
1. Wadia with an external dac--perhaps the best route--very impressive but depends on your dac--though can be used in analog mode
2. Red Wine Audio iMod -- see 6moons review -- only for generation 4 and 5 iPods
3. basic analogue iPod dock by Apple (best of the type), Belkin, Kensington etc
I've heard all 3 and definitely prefer the Wadia.