Using VMA-02 / KA-02 Sound Shield to get line-in input on arduino

I bought this VMA-02 audio shield: http://www.velleman.co.uk/contents/en-uk/p623_vma02.html

I want it to get the data from line-in to line-out but with reading it in my arduino scetch first (e.g. for analysis later).

There's a example project to download here: http://www.apogeekits.com/Zip_Files/ka02-sample-code.zip

But I don't know whether it's possible to get the sound input anyway and if yes, with which pins I can read the input / write the output?