I'm looking for a good book or website tutorial on the best/cleanest practices when developing an asp.net website from start to finish.  In particular, developing an object oriented website.  So basically, a book on the best approach to developing the cleanest, most efficient asp.net website possible.

 I'm not looking for any introductory books such as a "how to" work in asp.net, or c#, or anything.  I feel I'm already very well experienced in those languages however I currently lack the skill of putting all of those technologies together in a very clean, object oriented approach.

 Anything you can recomend?

Thanks.

Take a read of

ASP.NET 2.0 Website Programming: Problem - Design - Solution
Marco Bellinaso

http://www.wrox.com/WileyCDA/WroxTitle/ASP-NET-2-0-Website-Programming-Problem-Design-Solution.productCd-0764584642.html
great book, show's you how to build the beerhouse startkit site.

ASP.NET 3.5 Social Networking is  good book and uses some advanced topics like Domain Driven Design, Dependency Injection and Inversion of Control to build a complete ASP.net social networking site from start to finish. The BeerHouse book mentioned above is good as well and there is a new version with MVC just out. 

 Hey,

Have not read it, but ASP.NET 3.5 Enterprise Application Development with Visual Studio 2008 is a book in my queue and may be what you are looking for (Author Vince Varallo published by Wrox).

 I would look into this book Professional design patterns in vb.net:

Building Adaptable Applications  by

apress authors tom fischer , john slater

peter stromquist Chaur wu     

It uses GOF patterns and then you should start learning asp.net mvc

along with wpf                           

 I wanted to mention something else to you

Visual studio 2010 along with asp.net mvc will be using a lot of design patterns

decorator pattern, factory pattern. I would start to learn elementary asp.net mvc

first(There are a number of great tutorials on the subject) Asp.net mvc is great both

for web forms and silverlight(which uses ajax jquery) If you wish to buy a book asp.net mvc

in action(sept 2009) will be having  its focus in this area. WPF also uses oop techniques

as well so you see there is much to be excited about.   I hoped I helped you out....