You can import all the contacts from the various accounts into the one you choose to save. (See here.)
Then you'll have all your contacts in one place. Then send an email to all the contacts from the various accounts, telling them your master email address. Don't close the old accounts immediately, but set them up to forward incoming emails to your new account for a month or so until everyone gets the new address and is up to speed. You might get some stragglers that weren't on your contact list but you wish to remain in contact with. You can also forward any emails or files you wish to preserve from the old accounts to the master account. Then delete them from the old account. Clean up the old accounts by deleting unwanted emails and files, en masse if neccessary. (Learn how to select and delete multiple emails at once using the shift and ctrl keys if you don't already know how to do so.)
Finally, when you're sure you no longer need the old email accounts, simply close the account as described in this article
. and refer also to this article.
As long as you maintain the master account, you'll still have access to email, but once you close an account, it can no longer forward email to you. It is permanently closed. So take it gradually if you're uncertain, just to be cautious.
I hope this information allows you to resolve this issue. If you need further assistance, please post back with a comment to this thread.
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