I am going to start up a monthly contest but would like to know what would be a good script to do this providing there is one. I may need a custom one built.

How this will work is people will complete a sign up page and then they will need to find locations like blogs,forums or other sites that they can promote my site. Once they have add my link/s to a site then they would log back into my system and add the url to the site they promoted my site on. The system would then check to see if a url to my site exists if so then they would get 1 credit for it. Then at a certain date say the 25th of every month I could at a glance see who the leader is and then email the details on claiming their prize. The system would then start all over for the next month. So this way I could for a cheaper cost get people to advertise my site for me. Using say two prizes an 8gb iPod for first and a $100 gift card for iTunes for the runner up.Would run this monthly for a 1 year. Possibly also have a cash prize for a six month and one year grand prize winner.

I think this would be a lot cheaper way of promoting my site and the gifts would fit the demographic of traffic I am targetting.

Anyone see any flaws in this idea. Know of someone that could create the script for this or know of one that would work for it.