Got reunited with cast iron a few years ago when I scored on 3 different size skillets at a yard sale... Lodge and Griswold. They were $1 each and TOTALLY crusted with unknown GUNK. It took a lot of oven cleaner to get them back to usable... and well seasoned.
Since then, I've been a bit of a collector and have to restrain myself when I see a good deal. Everything I have came from a yard sale, flea market or thrift store and never paid more than $5 for any piece.
Bought a 2 burner Lodge grill/griddle for less than $5. Have a large, round griddle that's super slick. Have 3 "cron" pans. A Dutch oven. A cute little diamond shaped pan that makes perfect egg sandwich for square bread.
WOuld LOVE to find a DEEP chicken fryer and muffin pans and bread pans.
Are you a CI fan? My advice is USE IT, USE IT, USE IT... and it can become pretty much as non-stick as non-stick!