http://office.microsoft.com/en-us/outlook-help/insert-a-table-into-an-outlook-message-HA001034880.aspx

insert table icon not on in outlool 2010

http://answers.microsoft.com/en-us/office/forum/office_2010-outlook/insert-table-icon-not-on-in-outlool-2010/55be1a49-f647-4efa-acc2-61c7d0fcb1ef

the trick is to turn on
html

 rather than text