In the first meeting I mentioned we'll be bascially taking our "curriculum" right out of the MS Press books, following their chapters pretty closely. However, you can feel free to buy (or not buy) whichever books you feel work well for you.
I also mentioned that we should be getting a handful of books for free from our Microsoft Developer Evangelist, Peter Laudati. We're only going to be able to get about 5 or so, but Jim Morris had a great idea - everyone who's interested in buying one can pool their money together and we can use the free copies to lower the cost for everyone. I like it! Let me know if you're interested in participating in this, though it will most likely mean you won't have a book for the next week or two.