I have been working on an article for Codeproject for a while now, and I have just finished it. You can read more about this article at the codeproject link :Dynamic LINQ To Entities Queries Using WCF/WPF demo code
Those of you that have used LINQ to SQL may know that you can use variables and Func<T,TResult> against a LINQ DataContex, but may not realise that you can not serialise a Func<T,TResult> and that the “var” keyword is only method level scope.
This article talks about one possible approach of how to create dynamic queries against the LINQ to Entities framework, that are able to be sent across a WCF service domain boundary. The article uses a WPC Client that creates a dynamic query based on some reflection, which is then sent to a WCF service. The actual WCF service is hosted within a Windows service, and the WCF service will call the LINQ to Entities framework that in turn is setup to look at the SQL Server Northwind sample database.
I have gone through a fair ammount of extra WCF stuff/Windows service hosting in the article, so you may find some other information too.
Anyway hope its useful to someone.