I second (third?) clothdiapernation.com. And for the love of cheetos, do NOT go to diaperswappers.
Anyway, some of my favorite diapers were Thirsties fitteds and covers and also Green Acre Designs pockets. DS is a sloooow grower so we had a lot of the same diapers for a long time and those were the two brands that held up really well. Believe it or not though, I also loved my prefolds and they actually held up the longest out of all my diapers (we had the same PFs for almost 2 years and they are SO cheap). They're not really convenient for outings, but they're awesome for around the house. I would just throw a prefold on DS with a Snappi and skip the cover. That way, it would be breathable and I could tell right away when he wet and could change him immediately.