Orcs live in Sub Sahara Africa alongside other savage humanoids (including some humans). Feuds between many tribes keep Africa in a state of near constant war which has prevented Orcish expansion into other places. Over the last two hundred years, Orc lands have become colonies for the human kingdoms and many have been enslaved. Humans prefer half-orc slaves because they are not as strong and do not bitch about bright lights. Most kingdoms have lowered their slave quotas and prefer to keep them under servitude (have them pay off their debts of food and shelter through work).
Half orcs are exactly as in the SRD. They have regular aging tables, or human times 0.8.