Re: newbie help
You could get either premie or nb pf's. The premie pf's will only fit for a very short while, but the infant size can be bulky on newborns. You would have to fold the infant size down for a few weeks. With the fitteds and aio's you have already, I'd get about 24 prefolds - they can be used as inserts or doublers later, so they're a good investment. I just bought infants last time and dealt with the bulk for awhile.
As for covers, I'd get maybe 4-6 good wool soakers, but I'd also invest in some bsww or a similar pul covers, b/c with a newborn, you might not feel up to using wool all the time, although wool is great on little babies. I like to have 6 covers in each size.