99% percent of screenwriting contests are scams. The ones mentioned like the Nicholl are the exception. I'd avoid them all anyways and instead I'd show your script to friends and family and try and get some feedback.
My advice would be to take a look at:
https://blcklst.com/ . It's probably the only reputable screenwriting website where your money is actually well spent. I think it costs around $50 to post your screenplay on that website and you're guaranteed a read from someone who works in the industry. Along with reading your script the reader will also provide a review and some brief notes on your work. Feedback on your work from professionals is valuable and will be a good way for you to get an idea of where your writing talent is compared to other dreamers. On the off chance that your script is indeed exceptional posting a script to the website above gives you the greatest chance of breaking into the industry without any real connections to leverage.
Get as many eyeballs on your work as possible and then put a lot of effort into knocking out another draft or two of your current script. Then I would look to post it to the Blacklist website and see what happens.
There are many predatory businesses that prey on aspiring writers. Be careful to not throw away money trying to pursue your dream of screenwriting.
Last edited by Ahutz; 08-22-2015 at 12:05 PM.