I would like to have my 15 year old stepdaughter come for a month visit in October, I was wondering what form I need to file for a tourist visa. My wife is a permanent resident and we filed a I130 for her last year, but while we wait we would like for her to come and visit every year. Any suggestions?

Process should be detailed on the US Embassy in Bangkok's website. Each consulate handles the application process differently but typically begins with a form DS-156, DS-157, etc....