Recently the “Introduction to the Provider Model” whitepaper was updated at http://msdn.microsoft.com/asp.net/beta2/providers/default.aspx?pull=/library/en-us/dnaspp/html/aspnetprovmod_intro.asp. This is a must read for all ASP.NET 2.0 Web Developers.
This is a 10 parts, 120 page whitepaper and chalk full of awesome information on the inner workings of each of the new ASP.NET 2.0 Services. Each one of these Services will, by default, work with a couple of data repositories to store persistent data such as Membership, Role, Session State and Site Navigation to name just a few, but if the default repository does not meet your requirements then you want to read this whitepaper. This will no doubt become your best friend in learning how to inherit the respective base provider class to work with your preferred storage media, which is the beauty of the ASP.NET 2.0 Services in terms of it power and flexible model.