A little bird told me (well actually, a tall and rather glamorous bird told me) that Della Galton's fabulous Novel Writer's Toolshed ebook will be on promotion at just 99p from tomorrow (Friday).
If you haven't already read this one, it is well worth getting even if you don't intend trying to write a novel. It covers the differences between short stories and novels and whatever you write, it's essential to understand what works and what doesn't for your chosen length. Della herself reckons this is the best of the how-to books she's written. I think they are all excellent!
And if you are thinking about writing longer fiction, People's Friend are desperate for longer (4000 words) stories. Woman's Weekly are on the lookout for serials (10,000 or 13,000 words, in 3 or 4 parts). My Weekly and DC Thomson are always wanting more pocket novels. There are opportunities everywhere for all lengths. Della's little book might just help you get started.