Here
are some (hopefully) helpful links :
FictionpressFor posting your work. It's a pretty popular site, so a good way to get
your writing "out there."
CafepressIf you have a book written up, they'll publish it for you. The price
isn't much, and you can make a store on the site and sell your book.
PUSH Just write up a few chapters and
it might get you published!
Stone SoupA magazine that you can submit short stories to.
Excuse Me, How Much Did it Cost You?An essay on why you shouldn't pay someone to publish your writing.
Teen InkYou can submit many different kinds of work, and they might publish it
in their magazine, on their website, or in one of their books.
That's all I know. Post any you know, and I'll add them to the list.