I can still remember many people googling for " How to change email id in Gmail ? " . Even i googled many times and finally i have found a solution to it !
It is very easy and this hack will certainly help you :
It is not possible to change your username in gmail. The username is chosen at the time the account is created and is the permanent identifier of the account . But if you need to use a different username, it is possible. You simply need to create a new account and move your content over from the old account. For that :
Create a new account
Sign in to new account you just created and Hit the Settings link and then Accounts and Import tab.
You need to use POP3 entry. Enter the following configuration:
Username: Your old gmail email address
Password: Password for your old gmail account
POP server: pop.gmail.com
Always use secure connection: check
Label incoming messages: check
This will make sure all of your old mails along with recent ones continue to land upon your new email id . You can follow the instructions
Remember that if you delete an account, you can never get it back or reuse the address.