

First of all, go to google. Google is our best friend, hahah. ^^ Type in the name of the movie/play you're searching for an address to. Probably you'll find a lot of news articles and stuff about the movie/play/etc. you're looking for. Just try your luck and click on different links to see what comes up. Read fast through the articles etc. and collect as much as information as you can. (especially notice the dates they'll be there. There's no use in sending a letter if the actor you want no longer is there). If you're lucky, after a few searches you'll find the name of the studio/theater/etc. they'll be in. It might just be mentioned in a little note in the article, so if you don't find it in the big headline, don't give up hope. Read through the whole article. If you can't find the studio/etc. anywhere, try different searches like "*name of movie* studio" or "*name of play* theater". That might help. Once you've found the studio/theater they'll be in, you just have to find the location of it. Let's call our studio "ABC Studio" (just as an example^^), then you just try to search "ABC Studio location" or "ABC Studio address" and see what comes up. If you find the location address on your first attempt, do try to do some more research to be sure it's the right one. Remember, it would have been quite tragic to send to the wrong address! So be as sure as you can before you go ahead and send your letter. If you don't find the location/address for the studio/theater etc., try to search for it's homepage. Most studios/theaters have their own homepage. Just search for "ABC Studio homepage" and you'll most probably find it. There you'll most likely find an address for the studio/theater. And there you have it! After writing the name of the actor, the name of the movie/play, and the studio, you just fill in with the rest of the address. So, let's say our actor was named Smithy Smith (creative, right?^^), he was filming a movie called "The Beautiful Day", the Studio was ABC Studios, and it was located in New York City, NY. Then you just write:
Smithy Smith
"The Beautiful Day"
c/o ABC Studios
765 Wonderland street
New York City, NY 12345
USA
(Note: the address over is just an example! x3)
I really hope this was helpful. And if there's anything you want to add, let me know in a comment! Like I said over, I'm not a professional at all. Good luck with your collecting!
~Auroraluna