As promised, Apple began accepting online orders for the iPad 2 earlier this morning. At this point, all but one model—the 16GB Verizon 3G—is showing a shipment time of 2-3 weeks, meaning anyone who wants the device sooner will need to get in line at one of Apple’s stores or at one of its retail partner stores in order to secure a unit. Also available online are Apple’s iPad 2 accessories, including the $39 Apple Digital AV…