Robert Caron
Favorite Answer
You can't change an email id once it's created. But there is an option to add aliases to the existing account. To know about all the possible solutions,
Go to http://help.yahoo.com/kb/index?page=content&id=SLN2059&actp=search&viewlocale=en_US&searchid=1331749119455&locale=en_US&y=PROD_ACCT
All the best :)