We used Itty Bitty Buns fitteds, FB XS, XS VB AIO, Fun Organic Preemies and preemie IPFs. For covers we used Green Mountain and Prorap Classic in preemie size and Bummis classic wrap in NB. I understand Litewrap has a preemie size as well, but thir NB size runs big.
I used preemie prefolds and Proraps covers until he got to about 7 lbs, and was finally able to wear the Bummis SWW newborns (which I liked alot better than Proraps). We didn't start in cloth until he came home though, and he was 4 lbs 12 oz.