The stuff at Walmart is mostly Lodge.
There's also some foreign stuff on the market who's quality varies. If it comes from Australia, Europe, or S. Africa it can be pretty good. There's a traditional Afrikaner lidded pot with legs on the market called a 'potjie' that's really neat and quite functional.
Used cast iron is also an option. If something has much or questionable gunk, like maybe an excess of pork grease (some people don't eat pork), then you can strip a pan with a drill and a paint stripping disk or you can sandblast it. I've done both and it also works on stuff that has gotten rusty.
I've got some cast iron, such as from an outfit called 'Griswold' that was evidently made in the 1920's or earlier. The stuff is as function now as when it was new. One of them is a stove top waffle iron. Living low tech without waffles would be truly uncivilized.
Cooking with cast iron though, especially dutch ovens, is an art that takes some practice. If you're living at less than 21st or late 20th Century conditions, a couple of dutch ovens and the skill to properly use them can make life a lot nicer over the long run.
One thing I don't recommend getting in cast iron is a tea kettle. Get that in stainless or enamelware.