Connecting iPod to existing audio equipment

Hi all,
just been to Google Groups for this group and not seen anything
mentioned along these lines:

Got an iPod for Christmas, got (old) audio equipment in my car,
would like to connect them together if possible.
The options would appear to be either an FM transmitter for the
iPod, which seems like quite a neat solution, especially as some have
built-in chargers so that it can be plugged in to the cigarette lighter.
However, some reviews I've seen say they don't actually work too well.
Anyone had any good experiences? (This would be a useful approach as
it could then be transferred between mine and my wifes cars).
Another option would be a cassette tape adaptor (and my car audio
has a cassette deck - but my wifes doesn't....). Do these work well?
Do they vary in quality? (eg. seen them advertised from anywhere between
£2-£15). One downside is that I can't find one with an integral
charger/holder, so am thinking of a judicious and large blob of blutack
on the back of the iPod might be worth exploring

So, has anyone got any advice you'd be kind enough to take the time
to pass on?

Cheers,
MArlon