Swede,
Where in Central Kansas Are you? Lindsborg? I'm from that area too. You have some real big auctioneers at Salina, Hays, Dodge, and Hutch. When they have big estate auctions, you can find good old cast ware pretty cheap at those estate sales. My cousin works for the auctioneer at Salina. Look for the ones with slick bottoms. The ones with gritty bottoms from being cast, and the ones that have had the bottoms turned with a dull tool will never season right. The old ones have a pure slick bottom in them.
Even if they are grungy and rusty, do not fear, as long as they are not cracked or broken. Dutch Ovens should have the recessed lid for holding coals when baking. I cook taters in the inside and saute mushrooms in the lid.
If the skillet is clean, good. If it isnt, then scrub it clean all over and then season it. Beef tallow works best, lard will work too. Coat the skillit with tallow or lard and then heat it to about 400 till it quits smokin. You gettin the idea that the outdoor grill looks good? Otherwise you need a good stove vent, cause it will smoke. Grease it and heat it a couple times inside and out and it will take on the black castiron appearance. Dont let nobody inside that skillet with those dam green scrungy pads that end up in wimmens sinks. No scourin powder, just dip it in some soapy water and wash it out with the dishrag then dry it and heat it on the burner and oil it lightly. It wont rust and the black no stick will keep building up better than any store bought no stick cookware. If you make stew of whatever with tomatos, they can take your seasoning off, but dont despair, just oil it and put it in the grille and reseason it. It it kid proof.
If you cant find good stuff at the auctions, then in that area, look for Lodge. I dont know if Hutch or Salina has a Crackerbarrel restaurant, but they usually have a good selection of cast iron, and it will be Lodge.