Yes, we've got you covered here:
eas Auxiliary Audio Input
http://www.europeanautosource.com/pr...roducts_id=630
You will need the Digital DSP adapter also, this will replace your CD Changer if equipped. Your only other alternative is to upgrade the radio tuner ($500+) and use the AUX kit if the CD Changer is key.
Otherwise, ditch the CD Changer and go the DICE route with your iPod - this will integrate the iPod
and provide an AUX input:
DICE iPod Integration Kit for BMW - DSP
http://www.europeanautosource.com/pr...roducts_id=284
You've now got a few options - let me know if you need additional help.