Here's something I found, I went to the Ars Magica shop, went inside had a look at the items and then for some reason reloaded to before I'd gone in.
I went back in and there was a book for sale which taught me the "freeze" skill, I now have Freeze at 4, one above the max for my level, excellent!.
So there's a newby tip for you, reload at the Ars Magica shop until you get something tasty!.