The following is a best practice in organizing your Outlook folders before a migration to Google Apps. Gmail does not allow Inbox Sub-folders.
If you are using Google Apps Sync for Outlook you can create Inbox sub-folders. However, when you view the sub-folders in Gmail they will appear as one label Inbox/Sub-Folder
We recommend you create a new top-level folder called Received. Put all of your inbox sub-folders in this new top-level folder and you'll be all set.
1. Right Click on the top level folder in Outlook.
2. Left click and choose "New Folder"
3. Name the Folder Received and click OK.
4. Click and Drag Inbox sub-folders to the Received Folder
That's it, Way to Go!