For young basketball fans, NBA Hoop Troop is a great website. Much like the general kid sports sites, there are games and videos. However, unlike the more generic sites, there are also pages of stats, standings, team descriptions and even a page full of stat leaders.
There is also a link to WNBA info. It is a much more detailed, much more information based sport's site.
One feature of the site that some parents may not like is the store, though there is a warning to kids to get their parents permission before entering. Overall though, it's a very informative, very entertaining site.