I think your attitude is great!
First, a little story: When I announced my first pregnancy, my sister-in-law gave me about half a dozen pregnancy/parenting books of hers to read. When she left the room, my brother leaned over and whispered "You can read all the books you want now, but during the moment of truth, you'll do whatever works."
My point is that I think it's smart, especially as a first-time parent, not to have too many preconceived notions about what your baby "should" be like or what kind of parent you "should" be. After my brother's little missive, I realized that I would be better off letting my child's and my family's needs guide how I parented rather than making all kinds of ultimatums like "My child will never do X!" That's not to say that I haven't referred to a book or two since she's been here when I needed some advice. It's just that I've seen too many of my friends fret needlessly because their children weren't meeting whatever artificial milestones the books said they ought to be meeting at any particular time, or "weird" behaviors that were just their babies' personalities asserting themselves.
As for shopping, well, you may find as you get closer to delivery that your nesting instinct may make a bit of baby shopping more attractive!
But one of the nice things about not knowing the baby's sex (I didn't with my first) is that you really can't go too overboard on clothes before they're born, since so many of the more fancy/expensive infant outfits (i.e, things other than onesies and T-shirts) are not exactly unisex. This actually ends up being a good thing, since they so quickly grow out of the smallest sizes (and if you have a particularly large baby, they may not even fit in the 0-3 month size stuff when you bring them home!).
Anyway, I would say not to worry about not worrying. ;-) Newborn babies have a few, specific needs that I'm sure you don't need any expert to tell you about (I mean, you're not going to diaper his/her head, right?)
. The rest you can figure out as you go.