To add navigation links on any area navigation bar ( trial / members etc) you'll need to edit the template file header.tpl on line 316. For the tour navigation bar you will need to edit /tour/header.tpl begining on line 121.

We highly recommend using template fields for the text areas of the navigation bar so they can be changed at a later date and so that they can have support for multiple languages.

Please let us know if you have any questions about editing the navigation bar links by opening a support ticket.