I’m not a great one for entering writing competitions. More often than not you pay, you enter, you get an acknowledgement if you’re lucky and that’s it. On the other hand there are scores of places you can submit your stories without a fee and – if you target them – stand a good chance of getting published on-line and maybe even in print. And even if you don’t get published you may very well get useful feedback on your story.
I have found Duotrope to be a great help in finding places where I can submit my work. It’s a database of writing markets, updated weekly. Admittedly it’s biased to US markets, but quite a few UK and other on-line and print mags use it. Take a look.