I grew up cooking on cast iron pans and I've recently converted my fiancée to use them, too. Although we've typically used steel pans while camping in the past, we're about to switch to cast iron in the field. If I have any advice to give on this subject, it's this: go to eBay or antique stores and purchase a good quality Griswold, Victor, or Wagner size 8 or 9 skillet. It's a common size and they can typically be found for $20-$30. I say this because the quality of these pans FAR SURPASSES those of Lodge or any of the Chinese knock-offs you'll find new for the similar price. Check the inside of a Lodge pan- it's bumpy and pitted. Now check the inside of a Griswold- it's smooth like glass. That means less scrubbing to clean it and less time seasoning. Lift up a Lodge pan and it weighs a ton, where a Griswold is easily a pound or two lighter. Better metal, better finishing, and the fact that it's still around since the 30's is testament to it's durability.
Also- if you're into conservation, this is a perfect example of reduce, REUSE, and recycle!