You are talking of converting your local resources into Global resources. What you have right now is local resource files.
Read about them on how and why they are structured in a given manner:
MSDN: ASP.NET Web Page Resources Overview[
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MSDN: How to: Create Resource Files for ASP.NET Web Sites (Visual Studio) [
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You need to decide and then do it from start whether to have local or global resource. The way you can access the resx files depend on how and where they are placed. Collating at one place is possible if you make it global in App_GlobalResources folder. AFAIK, there is no easy way to convert the local into global ones. You need to do it manually, one by one.