Is there any way to build an adapter to link a small HD style MP3 player similar to an IPod to perhaps an input for a cd changer on an aftermarker deck?

I dont want to spend 100$ on a wireless transmitter or ipod adapter, but I think this would be possible.

The deck would recognize the mp3 player as a whole bunch of cds.. maybe?

 

Does the deck have an aux input, or only a changer input? What kind of deck and what model?

What do you mean it would recignize the mp3 player as a bunch of cds? Using an aux input, you would simply turn your radio to aux and use the mp3 player itself to change your songs.