Accessify.com - Accessible table builder - create accessible HTML tables that conform to Bobby and Section 508 requirements
Accessible Table Builder

This is in 'wizard' mode, and will take you through a step at a time. If you prefer, you can set all options on one page (requires JavaScript)http://www.accessify.com/tools-and-wizards/accessible-table-builder.asp
http://www.accessify.com/tools-and-wizards/accessible-table-builder_step1.asp