when displayed winner prize structure?

March Challenge 2013 already finished, but not to view for winner prize structure.
When is it displayed?

I think you are probably looking for this: http://blog.codechef.com/2010/09/01/new-prize-structure-for-monthly-contests/

The money prizes don’t seem to have changed since that post (400 USD for 1st place, 300 USD for 2nd place). Someone from Codechef will contact you to ask you for details regarding the payment of the prize, but it might take several weeks before this happens (at least that’s what happened in my case the previous times I got 2nd place in a monthly contest).