What you probably want is an fm transmitter. These things are hit or miss. Just start trying them out (try to get from a store with good return policies).
You'll probably get the best sound (if you can call really call it that) is if you use one that connects to the 30 pin proprietary dock connetor. If you get something like that, make sure that it is specifically and compatible with the 2G Touch (if that's the generation you have). Some older accesories will only allow playback but not charging. You could get something that doesn't connect to the cigarette lighter at all. It gets powered by a regular battery (AA or AAA) and you plug it into the headphone port on the Touch. I don't really recommend it, but you can always try it out. These tend to be less expensive. Just buy from somewhere with a generous return policy. This actually hold regardless of the type you get.
I can't make any specific recommendations since what I currently use are not fully compatible my my 2G Touch (I also have a 1G). I use a DLO Transdock that fully works with my 1G (plays and charges) but only allows playback on my 2G. It will not charge it. There might be a newer version of it that will fully work with the 2G.
Hey all I'm back....
I am wondering again what is a decent car adapter. I have a Pioneer CD player currently installed in my car....I dont have access to the AUX port of my stereo so I think the only option is the cigarette lighter port. Any options would be lovely.

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