I had been getting an International Driving Permit, but never needed it so I stopped. The only time I've been stopped was for speeding in Iceland (those empty roads are WAY too inviting for a Chicago area native!) I didn't have one and didn't seem to need one.

But you can get one easily and cheaper - I think I paid $12 - from your local AAA office. They took the picture and did all the paperwork.

Marguerite in Chicagoland