Steve Nash flirted with New York, listened to Toronto and pondered a return to Dallas, in a furious recruiting period that threatened to tip the balance of power in one N.B.A. region or another. The answer at last came Wednesday evening, just before the fireworks began to fly: Nash is heading to Los Angeles, to join Kobe Bryant and Pau Gasol, in a deal that should catapult the Lakers back into title contention.
