The dock for the iPod adds a line-our jack to the iPod. You can also connect a charger to the dock at the same time. The dock for the iPod Mini allows the same capability.
At least two Sony CD/MP3 players (the D-CJ01 and the D-NE710) feature a line-out jack, in addition to the standard headphone jack. The line-out jack uses a standard 1/8" stereo plug (the same as used for a set of headphones).
I hope that helps.
does anyone know if there are any mp3 and WMA players available with line-out ability?? i know they are available with line-in for recording, but i need line out abilities.