Spurs are definitely the Starks. They are traditioned, consitent, and will always be near the top.
Lakers are the Lannisters obviously. Filled with glamour, gold, and drama.
The Heat are the Targaryen family because Chris Bosh is a dragon.
OKC is house Baratheon because they are known as the storm kings and are from the Stormlands.
Celtics are House Greyjoy, trying to get back the power they once had.
Nuggets are House Arryn, because they are in the rockies and the Arryn castle is on top of a mountain. The Eyrie is impenetrable and its really hard to beat the Nuggets at home.
The Clippers are House Bolton, recently establishing power over the storied houses of the Starks
David Stern is Littlefinger because he likes to fuck things up.