My local BestBuy's (2 of them, only two in Alaska) have plenty of both as of this morning. Target had some (did really look on which exactly). My local Walmart has a few of each black WiFi only's.
Curious, do you guys not have "Mom and Pop Authorized Apple Dealers" in the lower 48? We have a couple of different ones "MacHause" (their bread and butter is repairs, their shops are pretty gross in all honesty). And then the Alaska Mac Store, their store rivals the Apple Store (which we JUST got in late 2011), and the people their know quite a bit more than Apple Geniuses. The later had/has some stock of iPad's as well.
Oh if you are looking for 4G. Check out AT&T or Verizon (depending on what you want). Nearly all of my local AT&T stores have all of them in both colors in stock (we only have AT&T up here).
My closest one actually ended up holding one for me for Friday Launch lol. The ONLY thing I did like is that they opened it up, as they wanted to add it to my cell account (but I wanted them to anyways, as it is my Company Account).