The cheapest thing to do is go to the library and look up the most recent issue of Writer's Market. I'd peruse the section which pertains to publishers that are interested in what you write; for example, short stories, articles, fiction, non-fiction, etc.... Then it's the hard part. You have to write a query letter. There are usually samples in the WM; but they also have books which handle query letters specifically. You can also opt to go on an online forum where you can place your work and hope by some chance a publisher or agent sees it. I, myself, don't trust doing that; but then, I'm just like that about internet stuff.
lol
Whatever you do, be sure and read the guidelines the editor's set forth for their publication. Most prefer you call their office and find out exactly what needs to be sent (note: be sure and address it to the right person). They really hate unsolicited material, because they get piles of it. Always be gracious and thankful for their time, because they have to spend a lot of time reading through queries, outlines and writer's works.
I hope you the best Nia-chan. I love your little avatar, it's so cute.
Regarding the AU and the canon - can you be more specific. I'm not sure what that means without more of a reference point. I think I know what canon is, but I don't want to take the chance I'm wrong since I've never heard of AU.