s810

I have a 2002 E320 wagon with the stock stereo/tape deck and the Bose speakers. I love the car and could keep it forever but there's no way I'll survive with a cassette tape player as my only sound. Having a line in jack would be all I need to stay happy but I don't have one of those. Even one of those cassette adaptors would work for me except I need to close the door on the tape deck. I would like to be able to listen to my ipod or my portable XM radio while driving. What are my options? Is there something the Mercedes dealer can set me up with or will I need to go to an aftermarket product?