Hi paigeandpruerock
I'm assuming you've bought an aerogram/aerogramme?
http://en.wikipedia.org/wiki/Aerogram
The problem with using one of these is that you can't put anything inside it (e.g. SASE, photos ...)
They're only supposed to be used for writing a letter on the inside. The good thing is that posting them overseas is a lot cheaper than sending an actual letter.
If you're sending a request without SASE's or SAE & IRC's, these are a good idea. The bad thing is that it seriously decreases your chance of receiving a reply in the first place, and is not fair for the celebrity to be paying postage for everyone who doesn't send something for return postage.
It is highly recommended that you do send a SASE/SAE & IRC's with
all requests you send out, to increase your chances of receiving a reply, and is also a form of politeness. As such, these aerograms are not the best idea to use in order to send out a request.
I'm assuming you do know how to send a regular request within your country. It's a similar process to send overseas (except unless you can get stamps for the country you're sending to, you'll need a SAE & IRC's instead of a SASE). I would recommend going back to the post office where you bought your aerograms and try to have them exchanged for stamps to send your envelopes overseas, or IRC's for your SAE's (or a refund altogether).
Good luck! If you have any further questions, please feel free to ask!
nowandagain [rockon]