In June we answered a question on Microsoft accounts in Windows 8. In Windows 8, accounts are based on an e-mail address so that it is possible to sync information using the same account on different machines. This is done using the OneDrive (formerly SkyDrive) cloud storage associated with the Microsoft account. (It is still possible to create a local-only account, like in Windows 7, if you prefer.)
A member had created an account using her ISP e-mail account, but later decided she wanted to use a different e-mail address/account. You may already have a Microsoft account through a Hotmail account, Outlook.com, use of Windows Live services, or an Xbox account. It would make the most sense to use an existing Microsoft account if you have one, but otherwise you can use any e-mail address to create one.
For the SIG member to go about switching accounts, we first created a new account with her desired e-mail address. Then it was a matter of transferring data from the old account to the new account. The Public folders can be used as a holding area to make the transfer. While logged in to the first account, she first cleaned up her desktop by moving some files into proper folders. Then she moved the data in her Documents, Downloads, Music, Pictures, and Videos folders (in her home folder under Users) into the Public Documents, Public Downloads, Public Music, Public Pictures, and Public Videos folders, under \Users\Public. She also moved some Desktop shortcuts and some Internet Explorer Favorites into those corresponding folders in Public.
After logging out of the old account and into the new, she then made the reverse move from the Public folders into her new home folder. The last step was to delete the old account in User Accounts of Control Panel.