You can find and edit your email address under your profile settings.
You can access your profile settings from your Home screen by clicking the "Your Settings" link or from the menu by clicking on the down arrow in the upper right corner.
You will see a text field there with your current email address. Select to edit and then save your changes by hitting "Save" in the upper right corner of your Profile.
If you cannot access your account, please use the "Need help?" link on the menu to request more help recovering your account information.