Frommer's has been pointing out, for the longest, that there is no such a thing as an international drivers license. They believe it is a way of making money by the autoclubs.
If you ever need to show a valid license you have to show the original D/L from your state.
[See Frommers site on Int'l D/Ls comments:
"I work for AAA Carolinas, so I can only go by what is valid for AAA Carolinas. The International Drivers Permit is for US citizens abroad, not for Czech citizens in the Czech Republic. It is basically a translation of your American drivers license, it is not actually required in foreign countries. The following is quoted directly from
http://www.aaacarolinas.com "
------------------------------------------------
If you violate any driving law or regulation and you get stopped, you will have to deal with it like in the US: be polite, be patient, and listen to the cops who, generally, will understand enough English to see that your license is real.
On the other hand, if getting this translation (and not a complete one) of your real DL make you feel better, well, then 10 bucks will do it.