Both of the contests listed below close to submissions Monday Oct. 1st. Both have fairly steep entry fees, but may be worth considering.
The 2012 "Scare The Dickens Out of Us" Short Story Contest is for unpublished ghost stories, 5000 words or fewer. There is a top prize of $1000, and two runner-up prizes of $500 and $250. These prizes help to make the entry fee of $20 a little more palatable.
The 2nd Annual Weird Words Short Horror Fiction Competition is sponsored by the horror magazine Fangoria, and the top three winning stories will be published in the magazine. Other chosen stories will be published on Fangoria's website. There is an entry fee of $10 per story, but all writers whose stories are published will receive some sort of compensation. Stories must be unpublished, 2500 words or less.