Why not just buy a cheap home stereo? If you're after decent bass you could always buy a plate amp from www.partsexpress.com and mount it to the sub box you make at least that will run on 110.

As for the CD player there should be a diagram on the top of it. There will be some stuff you obviously don't need like power antenna or illumination.

Also you're going to have to get something to convert 110 to 12.