There is no entry fee and there are cash prizes. Details are below and here: http://www.short-story-time.com/short-story-writing-contest.html

1st Place – $100 plus a one-year membership to the CBI Clubhouse , which includes a 12-month electronic submission to the Children’s Book Insider newsletter, as well as full access to all Clubhouse content.
2nd Place – $75
3rd Place – $50
Short Story Writing Contest Rules:
1) There is no entry fee and no restriction on the number of stories submitted by authors.
2) The deadline for submissions is September 15, 2010.
3) Material should be submitted electronically on this page below.
4) You must be 18 years or older to submit an entry.
5) Be sure to include your name and a valid email address with your submission so that we may notify you if you are a winner. You do this by setting the notifications on the second page of the form. After you submit your story, a new page will open up where you can edit your story as well as set email notifications-don’t skip this step or we will not be able to contact you if you are a winner.
6) All entries must be in English, original, unpublished, and not submitted or accepted elsewhere at the time of submission. We reserve exclusive electronic rights to publish the submissions on our site in print, video and audio formats credited to you, the author.
7) Entries can be read online. Visitors to the website can vote on the entries and are encouraged to leave comments. Online voting and comments will be taken into consideration, but winners will ultimately be decided by the webmaster’s panel of judges.
8) Winners will be notified via email on or before November 1, 2010.

Visit the website for complete details: http://www.short-story-time.com/short-story-writing-contest.html