Hi, I've got the book. If you can PM me your email address, I'll scan and send it to you.
If you have access to books on clay modelling / sculpting, they have tutorials and step by step instructions on how to make clay figurines out of modelling clay. I've used those books and just used gumpaste or fondant to create the figurines (instead of clay of course). On first glance it looks like the cake is round and the girl is sitting on top of the round cake.
So you could do a round regular base cake and a smaller one layer cake on top of it and decorate the side of the top cake with the flower / ruffle tip (for the skirt). Then you could incorporate your gumpaste figurine into that top cake...Hope that helps...
Looks like the ruffles might be fondant or gumpaste cut with a small petal cutter and indented with the ball tool, then you just layer them around the cake. The top of the skirt looks like a round piece of fondant or gumpaste thats ruffled.