I am debating whether to buy my first MP3 player, but one thing I want is to be able to use it in my car. What are the possible ways to connect an MP3 player to a car stereo? I know they have cassette-adaptors, but my car stereo does not have a cassette tape deck so that is not a possiblity. I've also seen these "FM Trasmitters" but I'm not sure how they work. It looks like one end plugs into a cigarette lighter and the other, I guess, plugs into the MP3 player. How does that work? Does it send a signal to the car stereo or does it actually have to plug into the car stereo somehow? Also, approxiamtely how many hours of music can a 1GB MP3 player hold?