I haven't tried them, but there is at least one fabulous-looking white chocolate buttercream recipe in Rose Levy Berenbaum's Cake Bible. She also has adaptations for very large-scale (eg wedding cake) recipes for same.
I really like white chocolate, personally. When I use it in buttercream recipes it actually does something opposite of what you might expect. I think it cuts the richness of the buttercream very nicely. You can add it to any frosting recipe, just remember to work backward, adding butter cream to your bowl of melted chocolate, then incorporating the bowl of white chocolate frosting into your larger batch of plain frosting.
....good luck, I'm sure they'll love whatever you do with white chocolate.
I must join the chorus in praise of The Cake Bible. I have never made anything out of that book that didn't work. Furthermore, RLB's instructions might border on the anal-retentive but for first time users, this is great. It's only after several runs at a recipe they get tiresome.