Use existing contact for "Me" in Ice Cream Sandwich
After trying forever (the "me" profile was never synced and could not be merged), this worked for me:

Install the Google+ app.
Set it to sync contacts.
Open your contacts again; your contact will now be set as "my profile".
Seriously.

source: https://makandracards.com/arne/7763-android-4-0-how-to-set-me-contact-to-your-existing-contact