SIM card for eastern europe
 

We will be in Czech Republic, Hungary,Romania next month. We have IPhone 5. Is there a SIM card that will work in all those countries that isn't too expensive? We will want to call within the country a few times but also back to the U.S. Have never used a SIM card so any advice will be appreciated!

You can only buy prepaid cards, and international calls are generally not cheap on those. Plus, once you leave the country where the SIM card was bought from (for example, when you move from the Czech Republic to Hungary), you will have to also pay roaming charges, which again, are not cheap.

I would suggest going for a VOIP option (Skype, FaceTime, Viber), since there are lots of free wifi spots available (coffee shops, restaurants, hotels).

The SIM card is only useful if people need to call you. If you are the one making the calls, I would use wifi and VOIP.

Provided your iPhone 5 is unlocked and able to take SIM card from anywhere, just get a PAYG SIM card from any EU country, and chances are it will roam in all those countries, and since the costs are capped by EU, it won't be too expensive.

Should I buy in US or wait until I get to the Czech Republic?

If you can get in US, you can tell your friends what your new number is, but it will be much easier to get in Czech Republic and just text or email your new number.
Czech SIM cards:
http://www.prepaidgsm.net/en/czech.html

Any chance you are using T-Mobile? They offer cheap international roaming with their Simple Choice plan in some countries - including Czech Republic, Hungary, and Romania. It costs 20 cents/minute to call the US from there or to call locally, but calls to the US via WiFi (if your phone supports WiFi calling) are free. Plus you get free 2G data roaming on the local T-Mobile partner.

I used this last week in Germany and France and it was awesome. I don't think I'll ever buy a local SIM again for my phone - no need to, unless I'm going to be making lots of local calls within the country.

Otherwise, I'd probably just buy a local SIM for each country for local calls if you won't be making many. In 2012 I bought a Vodaphone SIM in Czech Republic for my unlocked phone so I could make local calls. In the past I have been able to roam with these local SIMs in other countries, but the rates are much higher and you use up the minutes quickly when roaming. Still, if you will be making only a few phone calls it may be sufficient. I know when I got to Italy from Slovenia, I could still use my Slovenian SIM in Italy for a few brief calls before it ran out of minutes and that was all I needed.