[cflsystems]

mail/html/order_invoice.tpl is the correct template but you will not see words "Australia Toll Free" - it is a language variable probably for lbl_phone_2_title (could be lbl_phone_1_title). You can delete it or comment it out by surrounding tha part you don't want line this {* code you don't want to show *}. The word invoice is also a language variable. You can change it by going to admin/langiages, choose your language, search for the lbl_invoice and edit the text