Adding a button to standard OWL

Hello Gurus,

How do we add a custom button to the Accounts OWL and act on click of it?

I see that the UI is not extensible like that.

The requirement is to select a number of customers from the list and click the button. The button click should call an action on the account business object.

Can we add an embedded component below the list, add a button and on click of that, call action on the BO. How do we get the selected rows (customer IDs)?

Any suggestions are appreciated.