It's all dumb luck beyond this point. All the B&M stores have exhausted their inventories, save a random surprise shipment here and there.
And all the Internet sites will be at the mercy of ordering bots and/or people on the inside who know exactly when inventory will be released and tell their friends when to log on.
Beyond last night the only way you will get a PS 3 is through dumb luck, a highly overpriced bundle, a mixture of the two, or via Ebay or Amazon scalpers.