Interview!(2)

I went my 2nd interview today and it took about 1 hr. I think they like me but as i said before the killer will be that i have no working experience in USA. It seems that they are still trying to find someone has more experience. Should i write a thank you letter back and meanwhile trying to convince them that i am the best candidate? Does anyone have a sample with which willing to share?! By the way, the interviewers did not give me their business card, can i send a thank you note to the president and ask him to pass my thanks? Thank you very much in advance. I really do hope that i can get this one.