How to Recover a Steam Account From a Closed Email Account
If your Steam account has been hijacked or suspended, you can usually recover it through email verification. However, if you no longer have access to the email address associated with your Steam account, this poses a problem. The only way to change the email address on an account you no longer have access to is to enlist the help of Steam's customer service by opening a support ticket. The more information you can provide in your ticket, the better your chances of getting your account back.
Create a support account through Steam. This account is separate from your regular Steam account. Choose a username and enter your current email address. For security purposes, it is recommended that your support account details not match those of your normal account.
Go to Steam's "Ask A Question" site. This site will provide you with an online form to submit a ticket to Steam Customer Service.
Enter your Steam account name (your sign-in name, not your in-game display name), the email address you originally opened the account with, and your current email address. Write a brief explanation of how you lost access to your account and that you no longer have access to the original email address. If you have purchased hard copies of the games registered with your Steam account, scan or take a picture of the product key on the game packaging. Attach the image file to the online ticket form by clicking the "Add attachment" link. If you have only purchased digital copies of games through Steam, provide your credit card number or your PayPal account details.
Select "Account Questions" from the "Category" drop-down menu. A secondary drop-down menu will appear. Select the appropriate login problem from the second menu. Your options for this issue are "Hijacked or Stolen Account" or "Suspended Account."
Click the green "Submit Question" button. A Steam customer service representative will contact you regarding your issue.