According to Talmudic etiquette, the host says the hamotzi blessing and breaks bread, then at the end of the meal asks one of the guests to lead the Birkat Hamazon or Grace (Berachot 46a). This is because the host will be more generous with the portions than guests would be if they were asked to dish out the bread.
Asking a guest to lead Birkat Hamazon also provides him with a chance to bless the host. Toward the end, there is indeed a blessing for the hosts of the meal. Sephardic and many Ashkenazi Jews still use the original and effusive Talmudic formulation: "May it be Your will that the master of the house will not be shamed in this world or in the world to come. He should succeed in all his property and all of his property should be successful and close to the city…"
Most Ashkenazim today suffice with the brief, "May the Compassionate One bless the master of the house and all that is his." May I humbly recommend adopting the beautiful and generous talmudic version?