A few months ago I had to mail copies of my previously published books to a publisher in England. I had a crash course in how expensive international mail can be. I didn't even use the quickest, most expensive postage solution.
Then a friend wanted to submit to a German verlag, or publisher. We both started looking into how to obtain German postage for the editor to send a reply back from Germany to the United States.
In case you didn't think about it before, you can't put U. S. postage on a self-addressed envelope for a foreign editor to mail back to you. You must use the postage stamp of the country wherein the publisher is located or use an International Reply Coupon, IRC, which is a can of worms most editors choose not to open.
If you're writing for the international market, and many of us are, either freelance, book-length, or both, you need to know your postal options.
Harlequin, based in England as most of you know, is the target for a lot of submissions. If you want to send a manuscript to them, you must enclose a self-addressed, stamped envelope for a reply from them. Everyone, including the publisher tells you to enclose an IRC, the infamous International Reply Coupon.
If you live in a small town, chances are you're greeted with a blank stare from the post office clerk when you ask for an IRC. Many of them don't know what you're talking about or if they do, the post office may not have IRC's available.
Don't bother trying to educate the post office employees. Even if you could get them to stock IRC's for you, many foreign publishers will toss them in the trash because their value, purchased in USD will be converted to local currency which makes them of much less value. Additionally, foreign editors usually hate the IRC if they even know what they are, and many don't. If you're set on getting IRC's and think it's smart to stock up, please be aware that each IRC has an expiration date.
It's easier to just go to the Internet and purchase the applicable postage which can be printed and enclosed with your manuscript package.
For the United Kingdom, Royal Mail is their postal service.
Germany is Deutsche Post.
For Canada, use Canada Post.
For any other country, use your favorite search engine. "Buy Country postage stamp" should do the trick.
U. S. Postage
Back to the United States Postal Service so I can tell you how to mail to an International destination without taking out a bank loan.
You can buy any kind of postage online, but deciphering the International requirements is a bit complicated. So here's the gist of it. For manuscripts, use the Priority Mail Flat Box that's marked "Domestic and International." You'll also need a Customs Form declaring the contents regardless of the value of the package. By the way, all international mail in Priority packaging is considered a parcel so you'll need Form 2976-A.
For letters or other information about mailing to or within the United States, the USPS site is chock full of information with examples to show you how to fill out the various forms. If you really want to know all the mailing options, print this USPS Price Guide.