Create Resource file using Visual Studio IDE
Copy the resource file into 12 hive resource folder
GetLocalized method from SPUtility to read the values from resource file
Syntax:
SPUtility.GetLocalizedString(“$Resources:<<ResourceFileName,ResourceKeyName>>”, “<<ResourceFileName>>”, lang);
Example:
SPUtility.GetLocalizedString(“$Resources:MyResources,FirstName”, “MyResources”, lang);
Sample Source:

