Writing a book

I'm fifteen and I'm writing a book, I just started, and I was wondering how can I get it out there when I finish? and where can you get paper that is the size of normal books like don't die dragon fly or Twilight

If you're talking about publishing your book, you have to confront a publisher with something called a query letter. This is basically a letter explaining who you are, what you've done, why your book is special, who it targets, and, of course, a brief synopsis (summary) of the story.
Now, it's not guaranteed that the publisher will even want to look at your work, sometimes especially if you don't have a literary agent working for you. Basically, a literary agent is someone who you have to query (a huge part of the business) and wait to see if they accept your work. This can take a very long time, eight to ten weeks for some of them. But you are expected to be patient. Anyways, if they like your story and want to work with you, they'll send it to an editor to be picked at and prodded (expect lots to be removed and changed), until it is as good as it can be. Literary agents know exactly which publishing houses will be interested in your work, so it's a good idea to have one. And remember, they don't (shouldn't) cost anything. If they ask for you to pay for things besides post-tickets, they're not worth dealing with.
Make sure that you are sending your query letter to the right person, in the first place. Someone who is interested in Romance will most likely trash your Horror proposition.
Basically, the rest is up to luck. You can't expect your story to be accepted to the first place you send it, so keep patient and work hard. Everything worth obtaining takes time. This is a tough business, and it's not like what TV portrays it as.
Remember the most important things:
1. Learn how to write a query letter, and make sure to include whatever the publishing house (or literary agent) asks for.
2. Work at getting a literary agent to represent you (some publishing companies will just toss your work without so much as a glance if they see that you have no literary agent).
3. Make sure that your work is as good as it gets.
4. Don't give up or be discouraged
I would highly recommend looking into this further, not on an advice website because many people have no idea what they're talking about when they advise you, but on the internet, in books, and anywhere else that you would usually gather information. Best of luck!!
PS. It's better if you finish writing your story before querying anyone.

well publishers are the ones that do that. try just typing it and you should be able to google publishers and those type of people. and see who you can send it to, make lots of copys of it and maybe send it to more then one publisher. good luck and happy writing.

This isn't really advice, but... I'm 14, and I'm writing a book too. It's so hard to focus on one story long enough. lol. But, when I'm done writing my book, my dad's going to give it to his friend who is a publisher for children's books. I'm excited...but I have to finish my story soon.

Traditional publishers just don't know a good thing when they see one. Not all traditional publishers actually made the BEST decision when it comes to choosing books. Do you know that several best selling authors have been turned down by publishers? Stephen King, author of Gone with The Wind and Chicken Soup have been rejected by publishers and were not even given the second glance.

It's fun that you get to see your book published with the same expertise and professionalism as the regular books that you see in bookstores.

Self-publishing entirely means that you get to retain full control of your book’s production and that it gives you the option to publish your work and claim authority of the photos that you have chosen to be published.

How to get started with publishing:
http://editorinchic.wordpress.com/2008/11/21/how-to-self-publish-an-overview
Download your free guide:
http://bit.ly/9rOjx

I have found this really neat website called http://www.webook.com, you can publish your story on the website and all of the webookers can read your novel, I have recently started writing a poem book there called Singed, check it out if you have the time... I only have one poem in it