NHibernate

Introduction
NHibernate is a port of Hibernate Core for Java to the .NET Framework. It handles persisting plain .NET objects to and from an underlying relational database. Given an XML description of your entities and relationships, NHibernate automatically generates SQL for loading and storing the objects. Optionally, you can describe your mapping metadata with attributes in your source code.

NHibernate supports transparent persistence, your object classes don't have to follow a restrictive programming model. Persistent classes do not need to implement any interface or inherit from a special base class. This makes it possible to design the business logic using plain .NET (CLR) objects and object-oriented idiom.

Links

 * NHibernate website
 * Hibernate
 * Download
 * Documentation
 * Databases supported by NHibernate

Using NHibernate with ASP.NET

 * A good guide is described here.
 * Try to use the solution called Open Session in View