Yes! The hotel where the wedding will take place has rooms for all our foreign guests. You can find the link under the "Hotel & Travel" section of our website by clicking "view" on there.
Lufthansa, LOT, British Airways, Alitalia, Air France/Delta (from US), Turkish Airlines, Norwegian (low cost to London and another airline from there), Swiss, Iberia. You can connect from pretty much any large city in Europe to fly Bulgaria Air to Sofia.
Bulgaria does not require US citizens/permanent residents to obtain a visa. You may have requirements at connecting airports or if staying in other countries outside of the EU zone. We recommend you look up the information on the respective country OFFICIAL embassy website. Most don't require it or you will need an easy transfer visa if going through AND staying in Turkey, Russia, some Middle Eastern countries, etc.
You can opt for a low cost flight to Europe with Norwegian and fly from there with a low cost airline to Sofia. Please be advised it can end up being more expensive depending on luggage allowances and other fees, so triple check what the respective airline charges for before going this route.
We cannot vouch for or against such options. We have only traveled transferring through Istanbul and has been an overall decent experience. Please be advised that Istanbul airport is HUGE and you may need more than 3-4 hours in between flights. We cannot give an opinion on other destinations that are past Bulgaria.