How do manga/anime drawers get their ideas?

Ok maybe the question sounds silly. I started to learn to draw Manga/Anime style several years ago, still not top but improved. BUT: scanning through the image boards, I see my biggest problem is, how do drawers think of all those poses?

I mean ok I can use a photo as reference or another drawing. It is not so much a technical problem, I can draw most poses with relative precision, I just totally lack the ideas. :((

So if any of you draw let me know how you do it, or if you know drawing ppl ask them, I'd love to know. ^^

I don't like American-made pose books, because they don't look like Japanese anime (and you can always tell the difference). Wapanese fag, and proud of it.