Mario Kart 8 launches on May 30, but if you want to make sure you have a copy reserved before then, your best bet is to pre-order. Amazon is usually my go-to place for recommending pre-orders, but they’re currently out of stock on Mario Kart 8 and there’s no telling when pre-orders will be open through them again.
That being said, Newegg has you covered with Mario Kart 8, as they’re offering the pre-order along with a $5 promotional card to be used on anything else on their website. It’s not much of a deal, but some cash back is certainly better than none, especially now that Amazon appears to be out of stock for their pre-orders.