A virtual flood of emails from MacDailyNews readers reports iPad 2 sold out shortly after going on sale at Target, Best Buy, Walmart, AT&T, and Verizon retail stores in locations across the U.S. Apparently, many of those retailers had extremely limited supplies and model choices. For example, many report that some relatively far-flung Target locations had just 5 iPads total and only one model (16GB Wi-Fi-only in black). Some – AT&T retail outlets, for example – had none in stock at all, instead referring customers to order online, which shows shipping estimates of 2-3 weeks.

Apple Retail Stores seem to have fared only slightly better. Extremely long lines (cough – Gene “Don’t Expect Long iPad 2 Lines” Munster – cough) have been reported (and photographed) nationwide. We have reports that many Apple Stores quickly ran out of iPad 2 inventory as they shuttled hundreds of customers through each store starting at 5pm local time on Friday evening. One common refrain: “I’ve been to them all, iPhone and iPad launch days, and this one had by far the longest line!”

Interestingly, from the reports we have, 3G AT&T models seem to have been the first to go at the locations we’ve heard about from readers. In some locations, white iPad 2 models dried up first, in others, the black models were gone almost immediately. Of course, we have no way of telling if those models were in shorter supply or if they were actually the most popular.

Apple’s Online Store currently shows shipping times for all eighteen iPad models of “2-3 weeks.”

Our takeaway: Apple iPad 2 launch was a major event across the U.S.A. Apple’s supplies were inadequate to satisfy extremely high demand and many customers waited hours on line only to be turned away shortly after 5pm local time. It’s a nice problem for Apple to have, but it’s a problem nonetheless. Apple needs to get more iPads made and delivered to stores yesterday. That statement will likely hold true for weeks, if not months to come.

Apple could have sold many, many more iPad 2 units than they did yesterday, if they had adequate supply levels. Apple either severely underestimated demand or their supply chain screwed up somewhere along the way and couldn’t deliver anywhere close to enough units to retail. The company turned away many, many thousands of disappointed potential iPad customers empty-handed yesterday. That is never a good thing.

One thing Apple should do immediately is bring back the availability tracker – by iPad model, please! – on their website, so iPad 2 hunters can find Apple Retail Stores that have stock.

MacDailyNews Note: If anyone has info about iPad 2 availability anywhere, please let us know below (after you snag yours).