Does Microsoft AdCenter supports Paid search and Ad networks ?

HiI have few questions related to Microsoft AdCenter. Does Microsoft AdCenter supports two types of ads. Can any one give me some clear explaination about what is PaidSearch and what is Ad networks.1.Paid Search2.Ad Networkslike Google supports.1.Paid Search2.Google display network.We are building a custom application which shows the reports to the customers about their campaign performance management, in order to develop the application do we have any way of creating a account and testing before using real client user accounts.I have gone through the MSN AdCenter site, but it seems that there is no such information, if any one knows about how to create an account and test our application, please throw some light on this topic.Thanks in Advance.SB Team.