Gmail , an email service from Google is the most ever using email service in the world.Gmail has lot of advantages and features over other email providers.Gmail provides access privilege to all Google products easily.
It can be big loss for you if your gmail account hacked by someone and you lost the control on it.Since all the other accounts such as blogger,adsense,adwords,orkut,etc. are related to this single email id.
1.Try the password reset
The easiest way to get back your account is the resetting of your password.You can reset the password by answering the secret queston or by sending a reset link to the secondary mail.You can start the reset process by following the link https://www.google.com/accounts/ForgotPasswd
2.By filling the recovery form
In most of the cases the password reset may not be successful,Since the hacker will change the security question and the secondary email address up on hacking your account.At this stage you can use the second method of password recovery as filling the recovery form.The account recovery form will ask you several questions and you have to fill answer for that questions.Some of the questions are,
1. Email addresses of up to five frequently emailed contacts
2. Names of any 4 Labels that you may have created in your account
3. List of other services associated with your lost account
4. Your last successful login date.
5. Account created date(It can be get here)
6. Last password that you remember etc.