As I was involved in finding different ways and means to tackle the above problem, I was able to find two products which seems to address my issue. I also posted this in our Sri-Lanka .NET forum and for almost 2 weeks there is no reply.

I felt that Design Patterns will not really be that friendly when it comes to dealing with pluggable business rules which are quite complex. There fore I turned into rule engines which will support this kind of complexity. One is an Open Source Rule engine which Supports ASP.NET 2.0. More information is here.

There is another tool here which I did not have a proper look. This of course you have to buy.

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