Barnes & Noble Nook arriving at Best Buy, will go on sale April 18

Looks like the e-reader wars are heating up, retail-style: we just found out that Target will be selling the Kindle later this month, and now multiple sources are telling us that Best Buy will start selling the Barnes and Noble Nook on April 18th -- a rumor we can back up with this shot of Big Blue's inventory system. We're also informed that units are arriving at stores right now, so keep your eyes peeled -- we're assuming an overeager stocker will let one slip out onto the floor sooner or later. You know you can take a photo and tip us right from the Engadget smartphone apps, right?