Me, I love cast iron pans, the non-stick ability is second to none. I have used a pan that came with my house that was 40+ years old, even took it with me in the Navy and used it for another 21 years. My parents have a cast iron pan that I grew up with, I could use it when I could hold it, they still have that pan as well.
The first task is finding a cast iron pan in Thailand, I understand there is shops in Bangkok and Chiang Mai that sell these pans, but in the south, no stores seem to carry them. So I turned to the internet and found a seller in Pattaya that sells these pans via mail. I bought my 12 inch from here and am very satisfied with quality. Have a look here if you are looking to buy a cast iron pan: http://raro.asia/pan-pictures/ The site even has recipes.
Now once you have a pan, or you found that humidity is rusting the pan, here is how to season a pan to keep a good non-stick coating on it.
First thing, heat your oven to the highest setting. Scrub off any rust you see, for rust on the inside, pour in some vinegar and add some salt, yes, salt. This will dissolve any rust. Rinse the pan well when free of any rust then dry with a paper towel. Coat the entire pan with lard, shortening, vegetable oil of your choosing, once coated, put in the heated oven upside down for one hour. After 1 hour, turn off heat and allow pan to cool while in the oven.
To clean a cast iron pan, never use soap, after cooking, while the pan is hot, add hot water and and lightly scrub with a rubber spatula, pour out water, and place on a low burner and use a paper towel to get any water out, turn burner off and lightly oil, done.