I inspected the iPhone forms of Windows controls for mocking and positioning items and couldn't find them. However, taking a few screenshots with the iPhone Simulator is quite simple. Below is what I did - I will update with a link to download the project a bit later.
As already mentioned, Apple probably won't like it, and won't let you release a product using their user interface style. However, for ridicule, nothing prevents you from doing this in Visual Studio - they still get their $ 99 and shrink the app store.

I am using Visual Studio since I am developing Monotouch without XIB and want to avoid going back and forth. For applications without XIB, designing with Interface Builder, in my opinion, is not much faster, but focused on Monotouch.