It's his feast day today, so here's the altar under which he's buried. The inscriptions reads, "The bones of St. Justin, philosopher and martyr". Hat tip to Minor Friar.
Here's a post I did last year about his description of how the early Christians worshiped.
Here's the ancient account of his trial and martyrdom in A.D. 165. And on this page you can find all his writings if you scroll down to "Justin Martyr".