I did it this way(a single src and res folder for all projects, different LauncherActivities for each market):
Copy your res and src folder somewhere like /sharedsources/
Make a three new projects for Google/Amazon/Samsung.
Delete the res and src folder from each project
In each project link to /sharedsources/res and .../src
Now make a three new activities:
e.g. GoogleLicensing,AmazonLicensing,SamsungLicensing
Google Project Manifest: set GoogleLicensing as Launcher Activity
Samsung Project Manifest: set SamsungLicensing as Launcher Activity
Amazon Project Manifest: set AmazonLicensing as Launcher Activity
Google Project: remove SamsungLicensing and AmazonLicensing activities from build(dont delete)
Samsung Project: remove GoogleLicensing and AmazonLicensing activities from build(dont delete)
Amazon Project: remove SamsungLicensing and GoogleLicensing activities from build(dont delete)
Done.
Export each Project.
Keep in mind that you have three AndroidManifests now, which need to be edited accordingly.
Also keep in mind that you should only have one project open at a time.
There is no reason for opening more than one anyway, since they share the same source...
Actually i did this to be able to swap between Linux and Windows (my sharedsources folder is on a shared hdd) only for 1 project, but it worked out very well for the different markets aswell.