This most likely means you have a 2nd AppleID that has this same email address listed as an alternate email address for it.
Manage Your Account at
http://appleid.apple.com
Check to see if any of your other email addresses or AppleIDs and family members email addresses or AppleIDs have your main email account associated with it as an alternate email… because if they do, it won't send the verification email since it's already verified to another account.
You may need to change your email account to a 3rd or 4th one to disassociate it with this one first; then on the Apple ID website there's a section that says: Not Sure if you have an Apple ID? Find Out >
This will help you find the name on the other account and if you cannot get in to that account you should be able to receive a password reset to it.
http://www.betadaily.com/2011/10/19/how-to-solve-apple-icloud-verification-email -problem/
If you cannot find the account you can try emailing iTunes and/or call Apple and check if they can find the account that is still associated with the email address you are trying to use for this.
iTunes Support - Email Option:
http://www.apple.com/support/itunes/contact.html
iPhone technical support: (U.S.)
1-800-MY-IPHONE (1-800-694-7466)
iPod, Mac and iPad technical support: (U.S.)
1-800-APL-CARE (1-800-275-2273)
(if you call they MAY be able to grant an exception to the phone support of your device due to it being an account problem or iCloud problem)