Sooriya, I guess, it might be better to model it based on how the categories (or the product reviewes) are implemented rather than the manufacturer's implementation. Categories and products have a many to many relationship, in that, a product can belong to multiple categories. So you essentially create a Store_State_Map table and a State table
With the database structures in place, you would want sub sonic to generate the appropriate classes for you and add them to your project. Then write the code to handle the database calls and stuff. HTH