Is supply to the point yet where you can just walk in and get one or is it still necessary to try to get there early on days of deliveries?
brah.
Yep, along w/some other mentioned at http://news.cnet.com/8301-13506_3-20057828-17.html?tag=topTechContentWrap;editorPicks.Japan and Hong Kong are coming online for iPad distribution so there will be more fingers dipping into the pie. What that means for local supplies is anyone's guess.
All Apple stores in the DC area sell out before even opening. Most folks get there before opening hours and wait (yes still). They get a paper ticket and are told to come back at 9pm for their iPad.
Other stored like Best Buy, Target, Radio Shack sometimes have it but stock is 99% zero after the first day of delivery because they take reservations.