Stock Stereo Question

I have the crappy stock casette player in my car, and want to try something. I see that there is an TAPE/AUX button. Has anyone tried to hook anything up to the back of their factory head unit and run off the AUX? I have a Creative Zen Micro (http://www.creative.com/products/product.asp?category=213&subcategory=214&product=10795) , and since I have been driving a lot lately (6+ hour road trips), I dont want to have to rely on the radio. Has anyone tried to put one of these (http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F007%5F002%5F003%5F009&product%5Fid=42%2D2551) to the back of the radio and run something off of it? Just curious if it would work before I got buying things and tearing the radio out of the car.

I've heard of small 12V FM transmitters that plug into MP3 players or CD players that your radio can pick up. They are becoming very popular.

Something like this http://shop.npr.org/catalog/Product.jhtml;jsessionid=NCUBNDXRRD5X1LA5AJSSFFA?C ATID=cat100001&PRODID=prod360027

i think the AUX portion of it is is you had a factory cd changer connected so it would allow you to switch from tape to CD Changer I havent seen anything that adapts into factory changer ports except for "Ice-Link" which is a cable that allows you to control an i-pod from your factory radio, and I also seen some cd changers (Aftermarker) it think the Neo Changer it comes with a ton of different plugs for various cars from Ford, GM, VW etc.. but other than that i havent seen anything else.

As for the FM transmiters everyone i talked to that used them say they suck, if you have to use one you are better off using one that requires you to hardwire it and it has a antenna that plugs into the radio's antenna in, and then your factory antenna plugs into the FM modulator so you can still receive regular radio.

Thanks, I will look into that stuff. I Was thinking that there was just 2 rca plugs in the back that I could tap into. Oh well, so much for that idea.