Google has Nexus 4's back in stock, at least for a limited time. The estimated ship time is 1-2 weeks, but Google is at least giving you the option of buying the device again. Previously, the web pages for the Nexus 4 8GB and Nexus 4 16GB had shown the device as "SOLD OUT" and didn't provide any way of ordering.
LG has committed to producing more devices as quickly as they can, though they have blamed Google for underestimating the number of devices that would be demanded. For $300, it's near impossible to find a better device that is unlocked and without a contract. If you're not completely sold on the Nexus 4, you might want to wait for MWC in February.
MWC should bring lots of new devices, some of which may be even better than the Nexus 4. You could also try and wait it out for the rumored Nexus 5, though that probably won't show up until Google I/O, if it even shows up at all. You can get the 8GB Nexus 4 here and the 16GB Nexus 4 here.