With this Ribbon thing it is becoming harder and harder to support people over the phone, because simply you do not know where everything is anymore. Where the heck do i find email signature in Microsoft Office 2010? Sometimes change is good, but why would Microsoft create this ribbon thing and not giving us an option to switch it to a legacy menu? Why would they change a system that is second nature to people?
Here is how to change the email signature in office 2010
Click on File -> Option -> Mail
Then you go from there.
Here is a a video that Microsoft provided
http://office.microsoft.com/en-us/outlook-help/create-e-mail-signatures-RZ102000409.aspx?section=2