If this blog is not already on your radar - add it - NOW! I know there are a lot of teachers who read this blog, so please cue your students into this one - regularly!
Writer Beware Blogs!
"Writer Beware, a publishing industry watchdog group sponsored by the Science Fiction and Fantasy Writers of America, shines a light into the dark corners of the shadow-world of literary scams, schemes, and pitfalls."
At the keyboard for this blog are Victoria Strauss, Richard White, and A. C. Crispin, though Victoria seems to be the main blogger.
The blog regularly posts alerts regarding scam and highly questionable contests, carefully reviewing fine print and bringing unethical and questionable behaviors to the surface. There are also many posts and continued conversations on the print-on-demand publishing phenom.
Writer Beware is on top of the issues, and if you have any questions or concerns about anything regarding writers being taken advantage of in contests, publishing, marketing, etc., this is the place and these are the people to contact. (Though review the blog archive first, as you may well find your answer there already!)