C# Geocoding using Open Street Maps to retrieve street number and postal code

I am interested in a set of code to integrate with my existing application that can return the street name, street number and postal code from specific coordonate (latitude and longitude). I am using this for an existing project. Existing project is written in C# so I am interested more in c# programmers. Problem is either Bing or Google does not seem to have detail data on Bucharest coordonates meaning only few coordonates return the number of the street also. So I need do retrieve street name and street number (and postal code if possible) using either the three known apis Yahoo, Google or Bing but also want to see if there are other free source reverse geocoding providers around like open street maps.