I am looking for a way to read an audio file and convert it to a vector graphic format, which I can use for example for Illustrator? I am working on the Mac OSX platform (10.5.8).
I don't know if it will output vector graphics but you might want to check out something like Oscilloscope and Spectrum Analyzer Software.
If this doesn't have anything built-in (which is unlikely) then you might want to look at raster to vector conversion software (for example). This type of software works well with line drawings (scanned engineering drawings for example) and your waveform might be suitable too.