I sent a letter to a foreign country.
Why don't you put up the letter from Kim Jong Il for online auction? I think somebody would buy it.
I’m going to write a very heated letter to Coca-Cola and ask why there is so much sugar in their products.
A hand paper is a letter because letters are generally written by hand on paper.
If you want a more graphic image, imagine writing a letter on your hand, and how much it would hurt to chop off your hand and send it.
The reading is double kun'yomi (body parts tend to make kanji in words change to a kun'yomi reading). Both kanji in this word had you learn that reading right from the start, though, so you should be able to read this word. Just watch out for the rendaku making it がみ, not かみ.