Well you can buy a tape adapter just about anywhere, those have been common for many years, but it's going to sound pretty crappy (about as crappy as... you guessed it... a tape) or you can buy an FM modulator and listen to your music wirelessly through the radio (which also doesn't give you great sound quality)
VW AUX adapters would plug in where the CD changer would normally plug in (in the trunk, or at the back of the head unit, depending on the adapter) which means you could not still use your CD changer unless you switched the connectors every time.
http://www.indashpc.org/new/adapters/car2pc-vag.html is a source for some very nice adapters.
If none of this is what you're looking for then you might try looking on a VW-specific forum, like vwvortex.
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But don't take it from me! here's a quote from a real, live newbie:
Quote: Originally Posted by Viscouse
I am learning buttloads just by searching on this forum. I've learned 2 big things so far: 1-it's been done before, and 2-if it hasn't, there is a way to do it.
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