Apple sold out of most of their stock over the weekend, but this of course varies by store. If you want a 64GB model, then I would say you could probably find one, although you may have to try more than one store. If you want a 16 GB model (like most of us) then you likely will have a hard time finding one. But again, this varies by region. Someone posted that their store in Tennessee had plenty of stock left of 16GB models. However, with my many stock checks over the last 48 hours, the stores here in Texas have very little left except 64GB.
I went to a Best Buy near Portland, Oregon yesterday. They were out of Minis, except for the white 64 GB model, but they had all six configurations of the iPad 4. I bought a black 64 GB iPad 4, upgrading from an iPad 1, and I couldn't be happier.