A "season" of TV has lost all meaning, particularly to networks like HBO. Season 1 of Entourage had 8 episodes, season 2 had 14. According to HBO this is the second half of season 3 (which will have 20 episodes), so you're missing a bit -- about twelve episodes which aired last year. The new ones start airing on April 8th.

The second episode of the Riches was good, although it maintained the mix of fun and serious tone from the pilot. I'm kind of falling love with that show a little, and its only barely started.