Local Email folders dont come up on new OS 10.8. What can I do? I just upgraded my from 10.6.8 to 10.8.5. However my local folders are gone. I just tried to use time machine to access them however the time line before I made the upgrade is in red. How can I access those local email folders?
On my MBA- 10.9.4 the "on my mac" mail folders are in the 

~/Library/Mail/V2/Mailboxes/


The Library folder is hidden since OS X Lion, so use the Finder's "Go To Folder" menu in the "Go" menu and enter that address.