I loved luvs with my first! But as Natalia said... start buying now!
Also, no matter what brand you choose the cost of diapers will add up. Each week, starting now, buy a pack of diapers. Start with a couple packs of newborn size and go up from there. It will help a lot when you have your baby.
I like parent's choice. It's the Walmart brand. My younger son has sensitive skin and they work great for him. Pampers is a good brand too but they can be expensive. I tried Huggies with my older son and he just leaked out with those.