Jackson

You can add the buttons using either the feature 'Button Group' or by writing some client side code in the custom content box.

You can find 'Button Groups' here:

Administration -> Advanced Customisation -> Button Groups

And you can create a button group for the CompanySummary action that include two buttons using the 'AddressList' and the 'phoneemail' system actions. The buttons will then appear under the change button on the company summary page.

Or you can create the buttons using Client Side code:

community.sagecrm.com/.../sage-crm-7-2-controlling-the-properties-of-new-buttons-adding-using-the-client-side-api.aspx