Depends on your length of stay really, under one year you should be fine on an international permit, any longer than that, then after three months (usually) you need to get a US DL. Best bet is to ask at the driver license office, where they are renowned for their attitude towards customer service (very tongue in cheek here, they are known to be absolutely awful to deal with).
Insurance you will need to sort out when you get there, there are so many different levels of coverage and so many companies......good luck.
Graeme