Answer:
I am someone you don't know. Who am i?
What's always coming, but never arrives?
The Black Pearl was this type of criminal seafaring vessel
What does someone else have to take before you can get?
Inside a burning house, this thing is best to make. And best to make it quickly, before the fire's too much to take.
I am the fountain from which no one can drink. For many I am considered a necessary link. Like gold to all I am sought for, but my continued death brings wealth for all to want more.