I watched a WCAC (THE conference in the DC area) girls varsity ref do girls AAU games this weekend. I expect I will see him in the WCAC again next winter. Other than a high powered summer league, I don't know where you will find this pace of play and skill level outside the top HS leagues or college. WCAC had the number 1 girls HS team in America, and was beaten in the WCAC final by a team with a freshman starter who cut her teeth (and continues to excel) in AAU. The other freshman regular on that team is also on her AAU team.
jrut is right that you will see things here that you won't in some school leagues - cause this is where the players are that can do those things, at least in my area
If you can't get WCAC (or your local equivalent) and want great players, AAU is the place to see and ref them.