You might try
www.spindleworks.com
Most of the stuff there is from the viewpoint of the Dutch branch of Calvinism. It'll also give some insight into modern Dutch Reformed People.
I would strongly reccomend that you try the Canadian & American Reformed Churches' website:
www.canrc.org
Here too, you can see how a conservative Dutch Reformed Church upholds their faith in the modern world. You can read their liturgy, form of governament, and even look at their psalter (which uses the exact same music that has been used since the time of Calvin.)
You might also take a look and a listen of the CD "Psalms of the French Reformation" at
www.amazon.com They will have samples of each selection on the CD you can listen to online.
Even though it is in French, it is the same music that all early Reformed Christians used. The words would have been translated into Dutch, German, English, and Polish, but would have retained the music. It would give you an idea of what the public and private worship of historic Calvinist sounded like.
Most of the music, if not all, was written during a time of persecution for Protestants. I think this definately comes through in the melodies. I find them all hauntingly beatiful, and well worth a listen.
Hope that helps, and hope the project goes well!