Just did a scouting trip of my local Wally world this past Friday to get a snapshot view of the situation at the moment.
Basically, for non-shot cartridges, if you don't have anything that shoots .22-250 or .243, you're screwed.
There was an assortment of .410 and 20 gauge shells -- they all looked to be either target or bird loads.
"When newspapers are controlled, it's amazing how ignorant and immune from pressure the government can be." -- Amartya Sen