Help with converting analog to digital w/ garageband

[HeadSouth]

Sorry, I posted this under technique instead of recording last time. The post was:

This is driving me NUTS. I play mostly low fidelity stuff recorded with an old four track and some vintage mics. My four track has Line Out L and R and Line In L and R. My MacBook Pro has an Audio Line In/Optical Digital Audio In port. I have a cable (I think it would work..?) that has the red and white L and R tips on one end and on the other end is just one black tip. I have the latest version of GarageBand and people have told me that transferring the data from four track to digital is possible using this technique. I tried and I can't figure it out. Any advice is GREATLY appreciated. Thanks!

[superbassman2000]

that sounds right, but there is one thing to look for...on the one black tip there should be some rings around the tip...if there is one, its mono, if there are two, then its stereo, and you probably want the two rings

then you would plug that into the audio in jack

the red and white jacks are RCA jacks, which your 4track might have, otherwise you will need an adaptor