Adult Mail = Bills. Bill have postage paid.
So, I was able to get one stamp off of a birthday card and the rest of the page is inspired by other people sending letters.
“Harry picked it up and stared at it, his heart twanging like a giant elastic band. No one, ever, in his whole life, had written him. Who would?… Yet here it was, a letter, addressed so plainly there could be no mistake.Mr. H. PotterThe Cupboard Under the Stairs4 Privet DriveLittle WhingingSurrey.” J.K. Rowling
“He held up the envelope in which Mrs. Weasley had come… Every bit of it was covered in stamps, except for a square inch on the front, into which Mrs. Weasley had squeezed the… address. ‘She did put enough stamps on it, then.’ said Harry..’” J.K. Rowling
“Strange as it may seem, I still hope for the best, even though the best, like an interesting piece of mail, so rarely arrives, and even when it does, it can be lost so easily.” Lemony Snicket
“You deserve a longer letter than this, but it is my unhappy fate seldom to treat people so well as they deserve.” Jane Austen