You will need to connect your MD to the computer's sound input via a 'stereo RCA male to stereo 1/8" male plug' cable (if you have an MD deck with RCA outs), or a stereo 1/8" male to male cable (if you have a portable MD unit). I'm not familiar with MacAmp, but any program that will let you record the audio in aiff will do. Then I guess you can convert it to mp3 via iTunes.
If you have the right cables, this may not cost you a thing!
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