These are not copyright free (they are taken from Gotteslob), but the music can be downloaded: http://www.kirchenmusik-im-bistum-osnabrueck.de/cgi-bin/download.pl. Go to 'Liedvorschläge' and click the appropriate liturgical time to download.

You will be given a document like this: http://www.kirchenmusik-im-bistum-osnabrueck.de/download/jahreskreis-c.pdf. The responsorial psalms can be found at the 'Nach der Lesung' sections of each Sunday.

A second collection is the Gurker Psalter by Christoph Mühlthaler: http://www.kath-kirche-kaernten.at/dioezese/orgdetail/C2624/gurker_psalter_christoph_muehlthaler. The website gives PDF's of the responsorial psalms and mp3 audio examples (accompanied by piano, but I think it sounds better with organ). I'm not thrilled by the compositions, but maybe it's something you can use. I believe Mühlthaler uses the texts of the Austrian lectionary.