Walk the beach of Imperia in the early morning to find high level equipment and weapons. Stand on the beach and press A. If done correctly, you should see a window with a treasure chest on it, and a message telling you that it is searching. There is no limit to how much you can find; you can acquire a lot of items if you have the time.

When you kill somebody out of the dueling ring, a coffin will appear where they died. You can attack it to get all of that person's items. Note: This will not work in a dueling ring.

In The Southern Expanse, go to the coastline and press A. You will see a window appear that will look for treasure. This is a great way to get items.