If you want your writing published you'll need to send it out ... but where? If you've not yet been published then cafelit or runningoutofink might be good places to try. They don't pay but that does have the advantage that competition is likely to be less fierce than some other places (although it doesn't mean they'll accept any old rubbish). It also means they don't have to charge readers, so both are good places to head for if you want something to read.
Understandably many writers wish to be paid for their work, even if it's just a token amount. In that case you can try here, or here, or here, or here, or here, or here. Again these are all good places to go for an interesting read.
You might like to try AlfieDog who pay commission so the amount you earn will depend on how many times your stories are downloaded. It's an excellent place to go if you want something to read - the best short story download site.
If you're hoping for a bit more cash you might like to try Pages of Stories who've just reopened for submissions as Ficta Fabula.
I know opinions are divided about publication without pay (stand by for a post and interview with an editor on this issue later this month). One thing I will say before that is that if money is changing hands then it should be going toward, rather than away from, the writer. Other than competition entry fees, please don't pay to have your work published. If it's worthy of publication you don't need to do that.
Oh and don't expect anyone to hand you money, or a publication credit, on a plate. You will actually have to submit your work.