International driver's permit expired in Spain — what should I do?

When I discovered mine expired (in Sri Lanka of all places...), I prepared a simple document authorizing a family member to receive a new one from the local Automobile Association. I emailed the document to my proxy along with a scan of my driver's license. He printed it out, went there, showed them the document (which was not verifiable AT ALL), and got the IDP within minutes. He scanned it and emailed it to me, and I printed it in high quality on a cardboard-type paper at a local Internet Cafe. He then express-shipped it to me. It took a week to arrive, in which time I was stopped a bunch of times (policemen stopping nice looking cars looking for a quick bribe is very common in Sri Lanka) and showed my version of the IDP. No one was able to detect an issue with it.

Not sure how US IDPs look, but where I'm from, it's a simple folded cardboard printout. My high quality printout was basically indistinguishable from the real thing.

I don't know about the legality of this interim solution, but I do know that it worked quite well. Since you actually do get a new IDP using this method, the serial number on it is valid and corresponds to your identity (hopefully it would never get to a point where this needs to be checked by anyone, but hey...).

Just recently visited France, and I was worried about a similar case (rental car website indicated I should have an IDP). I called the actual rental office and they said they'd be fine with my US drivers license. In fact, they mentioned that while the IDP may even be required, enforcement simply doesn't happen.

If you are renting a car - talk to the rental agency (hell even if you aren't, just swing by an airport - i.e., where foreign visitors would rent one - and chat with the clerk).

Europe, in general, will accept any roman-alphabet license from a respectable country. Germany specifically says so, England specifically says they will accept most licenses printed in English.

Rental car companies are likely to be flexible with English-language licenses, less flexible with Polish (unless the counter staff is Polish) and will decline anything east-Asian without the IDP

So unless you have done something really naughty like doing 120 in a school zone while drunk, it's unlikely you will have a problem if you get pulled over.

Now, that's the police. Insurance will be looking for any possible reason to deny paying a claim, so if you have an accident and the local law says an IDP is required, then they (insurance) can declare your claim void as you were driving without a valid license. The police just couldn't be bothered writing you a ticket for it.